Physics Paper One

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what are scalar quantities?
have size(magnitude) but no direction
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examples of scalar quantities?5
mass, speed, distance, energy, temperature
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what is a vector quantity?
has size, magnitude and direction
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examples of vector quntities?5
force or weight, velocity, displacment, acceleration, momentum
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if speed is zero what does that mean?
object is stationary
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formular for speed?
speed= distance/ time
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horizontal line means?
stationary in time distcne grapg
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what is acceleration?
acceleration is a change in velocity per second
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what quantity is acceleration?
vector
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equation for acceleration?
a= (v-u)/ time
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what is velocity?
velocity is change in distance per seconnd
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what quantity is velocity?
vector
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formula for velocity?
v(2) -u(2)= 2 x a x X or v(2)= u(2) +2ax
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what does it mean if value for a is a negative?
slowing down
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what does the slop or gradient tell us?
acceleration
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what does the area under the graph tell us?
distance travelled
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horizontal line in velocity time raph?
constant velocity
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how can you determine speed?
using light gates and other equipment
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what is acceleration due to gravity?
9.8m/s(2)
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speed experiment?
ramp with light gates and cart s=d x t
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what is newtons first law?
body would remain at rest or continue in straight line at a constant speed as long as the forces acting are balanced
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what does it mean if resultant force is on object is zero?2
stationary or travelling at constanct speed
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what would happen is the resultant force would be acting in the opposite direction to the movement of body? 2
slow down or reverse direction of motion
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what is newtons second law?
when resultant force acts on mass then there would be a change in velocity
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what does the resultant force determine?
determines the size and diretion the subsequence acceleration of the mass
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how to find resultant force?
add parallel forces
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formula for force?
f=ma
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what direction is the acceleration?
acceleration is in the same direction as the force
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what is acceleration is resultant force is zero?
acceleration is zero
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what does a negative force mean? 2
object is accelerating backwards or slowing down
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what is the inertial mass? force over acceleration
a measure of how difficult it is to change the velocity of a moving object
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what is weight?
weigth is the force that a body experiences due to its mass and size of gravitational field it is in
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what is weight measured in and by what is it measured?
newtons(n) and newtonmeter
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what quanitity is weight?
vector
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what is mass?
mass is a measure of the amount of matter that is in a 3D space
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what quanityt is mass?
scalar
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what is mass measured in?
kilograms(kg)
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formular for weight?
weight = mass x gravitational field strengths w= m X g
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what does the gravitationl field strength deend on a body? 2
mass and radius of body
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what gravitaionaal field strength would abody have if they have a large mass and a small radius ?
large gfs
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if a body moving in a circular path with constant speeed will it have a changing velocity?
yes
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what quanityt is speed?
scalar
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what quantity is velocity?
vector
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what deos the velocity of a body change?2
speed change or direction of motion changes
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what is a centripetal force?
force acting inwards along the radius of the circle
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at what angles does the body move?
at right angles 90 degrees
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examples of centripetal force of gravitational force?
orbiting sattelite
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frictional?
car on roundabout
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tension?
a hammer thrower
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eleotrostatic?
electron orbiting nucleus
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where must centripetal force be acting?2
right angles to the direction of motion and towards the centre of the circle
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what does the moment of a moving object depend on? 2
mass and velocity
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what quanityt is momentum?
vector
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formular for momentm?
momentim (kg m/s) = mass(kg) x velocity(m/s) p=m x v
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what is a fore reagring to momentum?
force is the rate of change of momentum
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formula for force(mometum)
force= change in momentum/ time taken for change f= mv - mu/ t
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what is newtons thrid law?
every sction there is an equal and opposite reaction
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what do action force and reaction force act on?
different bodies
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where can third law be applied?
collisions
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is momentum conserved? explain why
momentum is conserves as total momentum equals total mometum after collision
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what is human reaction time?
time between a stimulus ocuring and a response
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what can the reaction time for humans be affected by?4
tiredness alcohol and drugs, distractions, age
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how can you determine reaction time?
ruler drop test
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equation for reaction time?
reaction time = /---------- 2 x distance / gfs
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what i9s the stopping distance?
the total distance over which a vehicel omes to rest
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what is thinking disatnce?
thinking time si distcance car travels before driver reacts ans applys brake
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what is braking distance?
distacne car travels while slowing down
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formular for stopping distance?
stopping distance= thinking distance+ braking distance
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thinking distance increases when? 3
driver tied, driver distacted, driver taken alcohol or drugs
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braking distance increases when? 4
frction between tyre and road decreases, road icy or wet, braked worn or tyres worn, mass of car is bigger
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give example for chemical store?3
fuel, food, batteries
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kinetic store?
moving ojects
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gravitationsl potential store?
raised mass
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elastic store?
stretches spring
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thermal store?
hot object
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magnetic store?
two magnets
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electrostatic store?
two charges
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nuclear stores?
radioactive decay
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what is a closed system?
where energy can flow in or out of system but no transfer of mass
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emergy transfer? 4
machanically(force through distance), electrically( electric current), thermal(temp), radiation(waves)
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what does thethermal energy transferred thriugh a wall of house depend on?3
difference in temp(warm inside cold outsied),thikness of walls, material wall made of
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how do most machines waste energy as?
heat energy
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what is effiecny?
way of saying how good it is at transferring energy into useful forms
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formular for effiecncy ?
effiecny= useful/ total x 100
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would amaterial with a high theraml conductivity be a better conductor of energy than one with lower termal conductivity
yes
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what are the main energy resources? 2
renewable, non-renewable
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name 5 renwable?
bio fuels, hydroelectricity, wind turbines, tidal power, solar cells
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what are bio fuels made of what does it prduce and what is it used ofr?
anikmal waster, thermal electrical energy, power cars
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explain hydroelectircyt?
water behined dam flowing down gerates electricyt
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explain wing turbines?
wind, kinetic energy, generates electricity
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explain tidal power?
uses rise and fall of tide to generate electricity
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solar cells?
uses sun rays which converst solar energy to electricity to cook food or to heat water
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two non-renwable resources?
nuclear fuels and fossil fuels
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what are nuclear fueld used for?2
genearte electrical, energy sources in spacecraft
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what are fossil fels used for?4
generate electricity, power transport and heats homes and for cooking
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what has changed over time?3
words population , development or technology(cars), electical energy (power stations rquire fuels ot generate electricity
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value of gravitational potential energy store depends on? 3
mass of body, gfs, hight what body rasied
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equation of change in gravitational potention energy(J)?
change= mass9kg) x gfs x height
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equation for kitetic energy?
KE= 1/2 X mass X speed(2)
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what is frwquency?
number of waves passing a point each second, hertz(hz)
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what is period?
time taken for one wavelength to apss a pint
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what waves are sound waves and seismic P waves?
longitudinal
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how do the particels move in a longitudinal wave?
particles move back and forth along same direction that sound is travelling -.-
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what waves are electromagnetic waves and seismic S waves and waves on water surface?
transverse waves
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how do particles move in a transverse waves?
particles move in direction at right angles to the direection the wave is trevleeling.ii
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2 ways in which longitudianl and transverse are similar?
both transfer energy without transferring matter, have amplitude , speed wavelngth, frequency
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3 differences of longidudial and transverse waves?
particels (long) virbraate along in direction or movemtn, transverse move at 90 degrees to direction of travel, have different speed , frequency wavlength
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speed, frequency, wavelngth?
v=f x \/
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speed, distance time?
z= x/t
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explain useing an echo to calculate speed of sound in air? 3
measure distance from source of sound to relfecting surafce, measure time involves between orginal sound and echo, use speed= distance/ time
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using two microphones and an oscilloscope?5
set up microscopes one in front of the otherm set frequency of sound from loudpseaker, sodplay two wavfoms in oscillion ope measure distance between the microphone, move micrphone apart fo waveforms move apart by 1 wavlength, wave speed= frequencyx w
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how to calculate the speed of ripples?
use a ripple tank and a strobe
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3 things how to use or what to use?
set power supply to vibrate paddle of known frequency, use shot light to freese water so can measure wavelength, speed= frwquency x wavelength
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what can the wave be once it reaches a boundary between two materials? 4
reflected, refracted, transmitted , absorbed
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when is sound transmited?
when densities are similar
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when is sound absorbed?2
depends on material and the wavelength of sound
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when is sound reflected?
when there is a big difference in the densities
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which waves can be refracted? 3
sound, water, light
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what is refration?
result in both speed and direction
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when does the direction not change?
if the wave fronts travel perpendicular to the normal
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when do sound waves travel faster?
travel slow in coller denser air that warmer less dense air
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when does water waves travel faster?
travel faster in deep water than shallow(able to chaneg direction)
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when do light waves slow down?
slows down and changes direction when pass from air to glass
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what frequency can humans hear?
20hz to 20000hz
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what kind of waves do energy trave;?
energy travels via a longitudianl wave until it reaches the ear
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how are sound waves produced? drum
after drum hit, vibrations of drum causes longitudial waves to movie outwards from it
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how does the ear detect sounds?
sound waves are chanelled through ear canal casues ear drum to vibrate, vibrations pass through ear as further vibrate whicha are converted to electrical signal and carried to brain
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frequency of ultrasound?
above 20000hz
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frequency of infrasound?
below 2o hz
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how can infrasound waves be detected?
from explosions under the ground
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wh tare ultrasound waves used for?
used to make image of the inside of the body
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what doe sonar uses to find deph of water beneath a sship?
uses pulses or ultrasouns
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equation to calculate deph?
distance= speed x time
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what happens when a sound wave moves fromone material to another?3
velocity changes, wavelngth change, frequecny not change
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what is the wavelength directly proportioanl to?
wave speed v
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what does the speed of sound in a amterial depend on?
the densty greater density greater speed
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what is the normal?
normal is a line drawn at 90 degreees to the mirror surface at the point that the arriving or incident ray meets the mirror
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what is the law of relfection?
angle i(incedent ray) = anglr r(reflected ray
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what is refraction?
change in direction of a light ray
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when does refraction happen?
when it travels from on transparent material into another
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why does refration happen?
because light waves travel at different seeds in different materials
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what does total internal reflection invole?2
reflection and refraction
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what is refration?
when light slows down and changes direction when travelling from less dense to more dense medium
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what angle is the angle of incedence?
criticle angle
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what is the light above the criticle angle?
light is totally internally reflected
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what are endoscopes used for?
to look inside patients bodies, and make use of optical fibres
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when does specular reflection occur?
when waves are reflected from a smooth surface
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will the reflected rays be parallel?
yes
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what does diffuse reflection occur?
when surface is not smooth and has rough irregularities(incident wave reflected at many angles, relfected rays not parallel
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how can we split the colours that we see?
using a prism
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why does a material appear green?
atoms relfect the green wavelength and absorb all of the others
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what do all colours have different?
wavelength
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what do filters let through?
different colors or light and absorbs all other colours
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green filter?
transmits green light and will absorb other wavelengths
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wha tare lenses?
pieces og lass that bend ligth in order to bring it to a focus
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the more refraction the more wht?
more power the lens has
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what are converging lens?
thicker in the middle
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how are diverging lenses?
thinner in the middle
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what does a converging len do to rays of light?
bends the rays of light owards one another forming a foacl point
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what does a diverging lens cause the luight rays?
bends rays of light away from each other
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the greater the power of lens the?
the more light it bends
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what is the focus at a point called?2
focal point or principle focus
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what is an real imagine?
an imagine that can be produced on a screen
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what does the focal length depedn on?2
thickness of lens, material of lens
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when is a real imagine formed?
when light rays converge and focused on a screen
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how is a virtual image formed?
formed by a converging lens wh nobject is between focal point and lens
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what lens produce a virtual image?
diverging lens
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how is a virual image formed?
by ligth ray whichappear to diverge from that point
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what type of image is formed by human eye?
real imgaine
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a magnifying glass?
virtual image
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all electromagnetic waves?3
transverse waves, travel same speed in vacuum, transfer energy to observer
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how to remember order?
red monkeys in vans use x rays glases
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longest wavelegntth toshortest?
radio to gamma
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longest wavelngth is lowest what?
frequecny
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what is the speed of light?
3x108m/s
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how do allwaves (lectro) travel in a vacuum?
with same speed
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electromagnetic waves may be? 4
reflected of surface, refracted material toanother material, trasnmitted pass throug material, abosrbed in different materials
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what types of waves are electromagnetic waves?
tranverse
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wha tare radio waves and microwaves used fro?
communication
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why cannot x-rays and gamma rays reach the surface of the erath?
they get absorvbed b the earths atmosphere
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what are the microwaves transmitted by?
by the ionsphere and re-transmitted back to the reciever
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what happens to the radio waves?
not trasnmitted by ionsphere they are refracted and then relfected to the reaciever
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what would abkects above absolute zero emit?
electromagnteic radiation
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factors affecting temerture?3
body constant temp abosrb same amount radiation at emits, object increase temo if absorbes more radiation than emits, object dcecrease temp if emits more ratiation thna absorbs
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what does the earth temerture depend on?2
how much raditaion is absorbed and how it is emitted
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gamma rays and x yrays 5 uses and 2 dangers
d- muations and caner, u- sterilise food and medical , scanners detcet cancer, treat cancer ,x rays , airport security scanners
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ultraviolet 3 d and 4 u
d-sun burn, skin cancer, eye problems, u- detcet secuityy masrks, isnide fluresent lams, detcet froged bacnknotes, disinfect water
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vidible ligt 2 u?
allows us to see, photograpy
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infrared? d1 u 6
d- skin burns , u- cooking, thermal energy, shrt rnge communication, remote controls, send info, security systems
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microwaves? 2 d and 2 u
d- heast water inside bofy, kill cells, u- mobile phones and cooking
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radio waves? u 2
broadcasting and communication
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what happens to radiation when electrons jump between energy levels?
absprbed ot emitted
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when do electrons move up energy levels ?
when they absorb energy
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when do electrons fall down to lower energy levels?
when they emit energy
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when do electrons move from llower energy level to ahigher energy level?
when the correct amount of energy is absorbed
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when do whe nis electromagnetic radiation emitted?
when electrons fall down from a higher to a lower energy level?
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what is emitted wh nenergy changes occur in the nuvleus?
high-energy gamma- rays
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what charge is the nucleus?
positive
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why does a nucleus have a positive charge
protons +1 while neutrons 0
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what percentage does the cleus conatin mass?
99
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th total number of protons is the same as the total number of what?
electrons
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what charge do the lectrons have
negative
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why are atoms always neutral?
positive charge from protons cancels out regular charge from eletrons
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what can the nuclues of an atom or an elemnt conatin?
different number of nutrients
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what is a molecule?
two or more atoms bonded to together
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what is the atomic number?
proton number number of protons
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what is the massnumber?
nucleun number number os protons ans nuclues
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top number is and bottom it?
top mass botton atomic
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what are isotopes of the same element?
atoms with the same number of protons but differnt number of nuetrons are isotopes
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when would an elcetron move lower to higher ortbit?
if it absorbes electromagnetic radiation
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when would an electron move higher to a lower orbit ?
if it emits electromagntic raditation
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why are some ions called positive ions?
becasue they lost electreons
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how can electrons leave an atom?2
absoring elecromagnetic radiation of eough energy to can escape pull of nucleus, being hit by a particle like alpha or beta
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alpha, beta, gamma, neitron radiator are emitted by what?
emitted by unstable nuclei
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why are some elements radioactive?
becasue the nuclei are unstavle
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when will unstavle nulcei decay?
when alpha beta gamma or netron radiation is emitted
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what is a alpha particel? charge and mass
i a helium nuclues becasue it 2+ mass 4
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what is a beta particle ? charge mass
an electron -1 mass 1/1840
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what is a positron ? charge mass?
ani-electron, +1, 1/1840
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what charges does a neutron have?
zero charge
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what is gamma ray? charge
form of high energy lectrogmagnetic raidation no charge or mass
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properties fo neutrons?3
not ionising, very high penetrating power, can travel through humsn and buildings for ions distances before stopping
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proeprties of alpha particles?3
travel around 5cm in aair, very ionsing, stopped by apaper
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propeertis of beta particles?4
travel few mertres in air, moderate ions, stopping by aluminium , 3mm thick
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properties gama rays?3
travel few kilometers in air, weakly ionsiing, thick lead stoped
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whichare effected by magnets fields?3
alpha beta(opposite direction to a and B+) ,positron
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what is bacjground radiation?
always being exposed to ionising radiation
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naural ocrruing br?2
cosmic rays, radioactivity from ground
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human activity br?2
nuclear power and medical(hspitals)
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plum pudding model?
circle with dits inside
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ritherfordfs model?
small postively charge nucelues
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bohr model?
elctton lead to orbit has positive neclues in energy level
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which way in a unstable nuclei, unfergo radiaoctive decay?
by beta decay
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what are thetwo types of beta decay?2
electron emitted, positron emitted
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what happens in B- decay?
neutrons decay to beome proton nd electron, proton sytays in nucleus. electron is emitted(b - paticle)
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formular B-decay?
P-> P + e-
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what happens in beta+ deacy?
protons in nucelues decays a neutron and positron , neutron stays in nuceus , positron(b+decay) emitted
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formular for b+ decay?
P-> n + e+
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when unstble nuclei decays what do they changes depend on?
depends on radiation
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alpha ? effect on mass an effect of charge?
mass reduced by 4, charge reduced by 2
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beta b- mass charge?
mass no cgange, charge increased by +1
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beta+ mass charge?
mass no change , charge reduced by 1-
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gamma ? mass and charge
no effect on niether
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neutron? mass and chharge
mass reduced by 1, charge no charge
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what are converves in a nuclear decay?
total mass and charge of nucleus are consvered
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what is the activity of a radioactive source?
the number of atoms that decay every second
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what is the unit for activity?
becquerel(Bq)
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what is half-life?
is the time it takes for half of the unstable atom to decay
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four uses of gamma rays?
kill cancer cels, sterilis surgical, diagnose cancer,
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what particles do smoke alarm contain?
alpha particles
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what makes the current fall in smake alarms?
absorption of alpha particles
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when odes the siresns sound?
when the current falls
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which particle are used to control thickness of paper?
beta particels
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what happens if paper is toothick?
not many particles get through so rolles preed it together mkaing it thinner
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how can atoms turn into ions?
ionising radiation knocks out electrons out of atom
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precution and saftey?3
limiting time of exposure, wearing prtective clothing,increasing distance between person and radioactive source
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what can cause mutations to us?
ios
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the greater the half- life the?
longer it will remain dangerous
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what is irradiation?
the exposure of a person to ionising radiation fro out side the body *cells can be damaged)
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whata re the two types of contamination?2
internal contamincation and external
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when does external contamination occur?
when radioactive material ion into contact with a person skin or clothing
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what is internal contamination?
when a radioactive source is eaten or drunk
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in which two ways can ionising radiation be used to diagnose illnesses and treat cancer ?
internally and externally
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what are medical tracers?
subtsnaces that are used in biological processes in the body and conatin radiosotope
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how can the subtance get into the body?2
eaten.drunk or injected
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what is the biological process?
it is monitered
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what can ionsising radiation emitted by the tracer?
be detected
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whats the radiactivity when the part of the brain is affected?
less radioactiveity is detected becasue glucose is not being used up
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what are PET scanners used to?
used to produce 3D colors
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what is the 1st step?
tracer(radioactive) decays quickly by emitted positron
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2nd ste p what happens when the positrons come into contact with electrons?
particles annihilate each other resulting in the formation of gamma-rays
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whatare the gamma rays detcted by?
PET scanner
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what are they pricessed by?
a computer
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do tracers decay quickly?
yes
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what can cancer tumours be treated internally by?
using a radioactive soource inside the patient
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the source enters the patients?2
injecting, eating or drinking it
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1 st to treating tomours ecternally?
beams of gamma rays are fired different positrons towards the cancer
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2nd?
damages the tumor, not stonrg wnough to kiil it)
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3rd?
mobing the beam amount of ionising radiation recieved by the surrouding tussue is reduced
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electrical energy can be generated in power station that use what?
nucleuar fuel
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whatare the three types of nuclear reaction?3
radioactive decay, nucelear furion and nuclear fission
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what from can radioactive decay be?3
alpha beta gamma
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what is nuclear fusion?
fusing of hydrogen nuclei in sun releases amounts of light and heat
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what is nuclear fission?
uranium nuclei spit by slow moving neutrons in a nuclear reactor, release amounts of thermal energy
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*** effiecent is a neclear power?
highly effeicnt at producing electrical energy
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what do nuclear power stations produce?
radiocative nuclear waste
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advatages of nuclear power stations?2
no co2, suplplies of nuclear fuel will lst longer that supplies of fossil fuels
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disadvantages of nulcear power stations?3
dangerous, accidenst can spread radio active material, difficuit and expensine to store nucar wste safteely
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what is the result in the fission of uranium-235?
release of a large advantage of energy
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what is that then used to?
heat water in power stations
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what happens in a fission reaction?
a large unstable nuceus splits into two smaller ones
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what does the fission of uranium-235 produce?
two dughter nuclei
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what is a controlled chain reaction?
when only one are neutron from each fission can casue other fission
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what is a chain reaction?
neclei may undergo fission and produce even more neutrons
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what ahppens if a chain reaction is not controlled?
there would be a nucear explosion
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what makes use of controlled chain reaction?
nuclear reactors
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how can a chain reaction be controlled?
controlled by using a different material t abosorb some of the reacytions
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generting electricity energy from nuclesr fission? 1 step
fuel rods(aluminium) undergo nuclear fission. thermal energy released
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2nd?
thermal energy from neclear fission taken by coolant to heat water and to produce steam
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3rd?
steam causes turbines to roatate which turns generators to geneerate electricity
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4th?
stem is cooled but into water in condenser so can be used again, therma lenergy eleased from colling
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what is a moderator usually made out of?2
graphite or water
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what does a conrete shield prevent?
prvents radiation and stray neutron escaping from the core
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what do control rods absorb?
absorbe neutrons
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what happens if control rods are pushed dwon into core?
moves neutrons are abosorbes so chain reaction slows down
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what happens if controlled rolls are pushed out?
fewer reaction are absorbed so chain reaction speeds up
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how nuclear fuel is sued in power stations?
nuclear fuel undergoes fission releaseing high qunitites of thermal energy which is then used to het water to produce
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what happens to products f uclear fission?
radiocative daughter produccts need to be disposed of safelty usually stored until the activity has decreased to a safe level
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what does nuclear fusion involve?
joining of smaller nuclei t form larger nuclei
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which is harder to supply a consitniuos supply of energy? nuclear fucion or fission
nuclear fusion
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when does nuclear fusion happen?
when small nulcei join to form larger ones
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what do fusion reactions rlease?
energy
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what is the equation for reaction in the sun?
21h +31h --> 42he +10n + energy
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what is electrostatic repulsion?
when positive charges on nuclei rpele each other
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what are the nuclei able to over come the elctrostatic repulsion?2
processors. very high temperaure
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what is very difficult to produce in a fusion power staion?2
very high temps, pressures
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what is nuclear fusion?
hydrogen nuclei fuse to produce helium nuclei and it also requires very large temp and a very high pressure and releases large qunitity of energy
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what is a nuclear fission?
uranium-235 spilts into two smaller nuclei and 2 or 3 neutrons, requires small moving neutron to be absorbed , releases larg quanitities of energy
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what does the solar sysem conatain?6
sun, eight planets, material satallites, dwarf planets, asteriods , comets
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order of planerts,
my very educated mother just showed us neptune
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what is the model from 130ce great ptolemy?
geocentric
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model for 1543 nicolasu copernicus?
helio centric
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what is the gerocentric model
earth in middle
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what is the heliocentric model?
sun in middle
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what type of bodies would bodies of lower mass travel in orbit?
bodies of much higher mass
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what were natural satellites formed by?
natural processes
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exmaplmes of natural satellites? 3
eight planet(rbit sun~), moons(orbit planest), orbits sun comets
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what are articial satellites?
heyare manufatures and have been launched into space from erath by using rockest
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explames of ariicial satleiites?3
geostationary orbits around earth for global positionaing, loiw polar orbits weather monie=tering, sent from eart monitor sun coments planets and asteriods in **
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how do sartificail satellites orbit?(son ,earth planets?
tend to move in circular ot near circle orbits
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how to comets trvael?
they travel in high ellptical orbits around the sun
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what happens to the speed and velocity of the comet?
it changes constantly
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what happens to the gravitational force of the sun acting on the comet?
it gets weaker as it gets faster away from sun
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when will the comet travel faster?
when it is closer to the sun and travel slower further from sun
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will the speed and veolicty change of orbit?
speed nt change velocity change as it is constanlty changing direction
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what would the gravitational force be on a body in a circular orbit?
would be the same at each point of orbit as radius is fixed
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what would happen in the earths orivtal speed increased?
gravitaional force from sun not keep it in orbit so fly out of orbit to know orbit of greater radius
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what would happen if ear5th orbitl speed decreased?
suns graiational field casue to all towards it into new orbit of smalelr radius
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what does the big bang theory state?
universe staretd out as a tiny articel (13.8 billion) years ago , still exapnded
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what does the steady state theorystate?
universe alwasy existed sill expainindg and new matter created as it expands
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when galaxies emit light when moving away from us what do they emit?
emi is red shifted
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faster the galaxy is traveliing from us where would the lines be??
near he red end of the psectrum
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what is CMB?
cosmic microwave background radiation(echo of bb)
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evidence for bb?2
red shift and cmb
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evidence for **? 2
red shift
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what do the doppler effectand the red shifprovide evidence fro?
nature of the universe
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what is the doppler effect?
when a wave source is moving relative to an observer there is also a change in the frequency and wavelength of the wave
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what waves does the doppler effect occur for?2
light and sound
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what would a ligh source moving away from an observer have?2
greater wavelengths and high frequencies(it is red shifted)
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what would a light source moving towards an observer have?2
smaller wvalength and higher frequecnies(blue shifted)
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low mass stars?1
nubula(dust cloud and hydrogen) pulled inwards because force of gravity as gas contracts nebula gets hotter
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2~?
hydrogennuclei fuse so nuclear fission leads to heavier helium model and energy is released, gives out light and is now a main sequence star(inward force of gravity is balanced by outwards froce of thermal
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3?
hydrogen gas converyed to helium star expands and becomes red giant core colapses heavier elements formed
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4?
nuclear fusion stops, due to fusion elements being used up star colapses becomes white dwarf
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what happens to a higher mass star when hydrogen is used up?
forms a red super giant
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what happens next?
explodes as supernova
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what happens to the remains?
pulled back together by gravity to form neutron star
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what would massive remnants form?
black holes
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fate of low mass stars?2
red giant to white dwarf
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fate hiogh mass stars?3
main sequnce to red supergiant to supernova
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development of telescopes?4
greater magnification, recording photography or digital cameras, greater precision, detect other parts of electromagnteic spectrum
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what happns to some part of the electromagnetic spectrum?
abosrbed by earths atmoshpere
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where would ultraviolet telescope need to be placed to detct ultrabiolet radiation?
in ornit
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what happns to some part of the electromagnetic spectrum?
abosrbed by earths atmoshpere
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where would ultraviolet telescope need to be placed to detct ultrabiolet radiation?
in ornit
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examples of scalar quantities?5

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examples of vector quntities?5

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Card 5

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if speed is zero what does that mean?

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