Physics P2
4.0 / 5 based on 5 ratings
- Created by: wafflypig
- Created on: 12-03-16 14:45
3 methods of car safety?
Seat belts, airbags and crumple zones
1 of 135
Properties of beta radiation?
Moderately ionising, quite fast, -1 charge, small mass, ejected electron, stopped by aluminium
2 of 135
Properties of gamma radiation?
Weakly ionising, very fast, no charge, no mass, EM wave, stopped by a few inches of lead
3 of 135
Properties of alpha radiation?
Highly ionising, very slow, 2 protons and 2 neutrons (He), heavy mass, stopped by skin or paper
4 of 135
Use of alpha radiation?
Smoke alarms, when current stops, alarm sounds.
5 of 135
Uses of beta radiation?
Medical tracers, thickness control
6 of 135
Uses of gamma radiation?
Treat cancer, sterilising medical equipment and food
7 of 135
Things that effect braking distance?
Speed, mass, quality of brakes, weather conditions (aquaplaning), grip
8 of 135
Things that effect thinking distance?
Speed, reaction time (drugs, tiredness etc.)
9 of 135
Define current?
The rate of flow of charge, measured in Amps (A)
10 of 135
Define work done?
Work is done when energy is transferred by a force moving an object
11 of 135
Define power?
The rate of energy transfer
12 of 135
How can a build up of static charge cause an explosion in a petrol tank?
The electrons are transferred to the insulator and held there, this build up may lead to a spark, light the fuel and cause an explosion
13 of 135
What is earthing?
Earthing provides a self route for excess electrons to reach the ground through a conductor (usually copper wire).
14 of 135
What is potential difference?
PD is the difference of electrical potential between two points in a circuits.
15 of 135
What is voltage?
The driving force of the current in the circuit
16 of 135
What is Ohm's Law?
Current and voltage are directly proportional; current and resistance are inversely proportional
17 of 135
What is Newton's 2nd Law?
Unbalanced forces acting on an object, results in a resultant force meaning there will be an acceleration. A greater resultant force = greater acceleration
18 of 135
What is Newton's 1st Law?
When forced acting on an object are balanced, the object will stay at rest or continue at the same velocity
19 of 135
What is Newton's 3rd Law?
Equal and opposite forces. When body A exerts a force on body B, B will exert an equal but opposite force on body A
20 of 135
How can charge build in a thundercloud?
Chunks of ice knock into each other, building up an electrostatic charge, resulting in a lighting strike
21 of 135
Advantages of nuclear power?
Uranium is abundant and cheap, it is reliable, safer than people think, doesn't burn fossil fuels
22 of 135
Disadvantages of nuclear power?
The waste has a long half life (dangerous for a long time), risk of leaks, overall cost is high
23 of 135
What is nuclear fusion?
The joining together of two light nuclei to form a larger nucleus, releasing energy. E.g. two hydrogen = helium
24 of 135
Describe the process of nuclear fusion...
It must happen at very high temperatures and pressures, must be in a magnetic field because anything else would melt.
25 of 135
Advantage of nuclear fusion?
Not much waste
26 of 135
What is nuclear fission?
The splitting of a large nucleus by firing a neutron at it to form two, smaller daughter nuclei
27 of 135
Describe how uncontrolled fission can lead to a runaway reaction?
There will be lots more neutrons so split up more and more uranium atoms which go on to split more and more, releasing more and more energy, could result in nuclear meltdown
28 of 135
How can a fission reaction be controlled?
Moderators slow down the speed of the free neutrons so they are slow enough to be captured by the uranium nuclei. Control rods (graphite/boron) are lowered as needed to absorb excess neutrons to stop a runaway reaction
29 of 135
Use of nuclear fusion?
In stars
30 of 135
Use of nuclear fission?
To power nuclear power stations
31 of 135
How is terminal velocity reached?
When an object falls forces acting on it gradually become more balanced. Eventually, weight will equal air resistance so there will be no acceleration. It will travel at a constant velocity.
32 of 135
Define acceleration?
The rate of change of velocity
33 of 135
What can the are under a V-T graph be used to calculate?
Distance
34 of 135
What is a negative gradient on a D-T graph?
Returning to start point
35 of 135
What is a curve on a D-T graph?
Acceleration
36 of 135
What does flat mean on a D-T graph?
Stationary
37 of 135
What does a curve mean on a V-T graph?
Changing velocity
38 of 135
What is a flat line on a V-T graph?
Constant velocity
39 of 135
What is the relative mass of an electron?
1/1860
40 of 135
What are the dangers of alpha radiation to humans outside the body?
None
41 of 135
Dangers of beta and gamma radiation?
Can penetrate skin and has potential to turn body cells cancerous or even kill them
42 of 135
How is aircraft adapted to cope with a build up of electrostatic charge?
Have black rods to expel excess electrons on back on wings (charge built up against air particles in flight). The have places for earthing wires to be connected under the wings and have insulating tires.
43 of 135
What is induction?
When charges on an object (e.g. wall) separate depending on the charge of the object being held near it
44 of 135
How does a balloon get attracted to a wall?
An induction happens
45 of 135
What are the 4 uses of static electricty?
Electrostatic dust precipitators, laser printers, photocopiers and defibrillators
46 of 135
What happens at junctions in a parallel circuit?
Current is conserved
47 of 135
Conservation of energy says that...
Energy can never be created, nor destroyed. It is useful when it is being transferred
48 of 135
Kinetic energy gained =
Gravitational potential energy lost
49 of 135
Gravitational potential energy depends on...
Height
50 of 135
Kinetic energy depends on...
Mass and velocity
51 of 135
What is the unit for acceleration?
m/s^2
52 of 135
How is the gravitational field strength on earth?
10 N/Kg
53 of 135
What is the unit for momentum?
Kgm/s
54 of 135
What is the unit for work?
Joule (J)
55 of 135
What is the unit for power?
Watts (W)
56 of 135
What is the unit for half life?
Bq
57 of 135
How can half life be shown on a graph?
Using a decay curve
58 of 135
How can the dangers of working with radioactive materials be reduced?
Hold the course at arms length, thick glass, lead-lined apron, robotic arms
59 of 135
How can radioactive waste be safely disposed of?
Vitrification, then put deep underground. Or, put in a thick metal container and bury deep under cement
60 of 135
The top of a thundercloud has which charge?
Positive
61 of 135
How can you get a shock from your car?
A charge builds between clothes and synthetic car seat when friction happens. Then touch the metal car door and current flows = zap
62 of 135
How can shocks from cars be prevented?
Have a conducting ***** hanging down from the back of the car for earthing
63 of 135
What is a DC?
A direct current. Current flows in one direction
64 of 135
What type of current do mains sockets provide?
Alternating current
65 of 135
How does an electrostatic paint sprayer work?
The paint gets a negative charge as it moved through the -ve charged nozzle so they are attracted to the +ve charged object
66 of 135
What are the advantages of using an electrostatic paint sprayer?
Droplets repel each other = even coat and no drips, attracted to all over the object, no waste, no paint shadows
67 of 135
How can an explosion be the result of a static charge?
Huge charge build - spark - ignites fuel fumes in the air = explosion
68 of 135
What does earthing do?
Stops the build up of static charge
69 of 135
Why are metals good conductors?
They have delocalised electrons to carry charge
70 of 135
Why does a voltmeter need need a huge resistance?
To stop the flow of current through it so it can get a true reading of the PD
71 of 135
What can be used to measure current?
Ammeter
72 of 135
Does an ammeter have to be connected in series or parallel?
Either
73 of 135
True or false, a voltmeter must be connected in parallel?
True
74 of 135
What does the cell in the circuit supply?
A push force of the electrons in the circuit
75 of 135
Why do electrons move when a cell is connected?
The positive terminal pushes electrons away (around the circuit) and then the negative terminal gives the electrons energy to get through the negative end of the terminal to go around again
76 of 135
What is a coulomb?
The unit of electrical charge, 1 coulomb = 1.2*10^18 electrons
77 of 135
What does the V-I graph of a fixed resistor look like?
Positive, straight and diagonal gradient
78 of 135
What does the V-I graph of a lamp look like?
An S
79 of 135
What does the V-I graph of a diode look like?
Exponential function
80 of 135
What is the unit of resistance?
Ohms (Omega)
81 of 135
Potential difference is technically...
The energy transferred per unit of charge passed
82 of 135
True or false, potential difference decreases over a resistor?
True
83 of 135
What happens in a resistor?
Charges release their energy
84 of 135
Why must an ammeter have a low resistance?
To not change the current (the thing it's measuring)
85 of 135
At a junction, the total current leaving is equal to...
the total current entering the junction
86 of 135
What is a LDR
Light Dependent Resistor
87 of 135
In bright light, what is the resistance of a LDR?
Low
88 of 135
What is a thermistor?
Temperature dependent resistor
89 of 135
In hot conditions, what is the resistance like in a thermistor?
Low
90 of 135
Why do resistors get hot when a current passes through them?
There is an energy transfer which heats the resistor. The electrons collide with the ions in the lattice which releases energy as heat
91 of 135
What does a fuse do?
Melt and break the circuit if the current gets too high
92 of 135
Electrical power is...
The rate at which an appliance transfers energy
93 of 135
A high power rating means...
Lots of energy is transferred in a short amount of time which draws more current from the supply
94 of 135
Give an example of a scalar quantity
Speed, time, mass
95 of 135
What is a vector quantity?
A measurement that has size and direction
96 of 135
What is displacement?
The distance between two points, regardless of distance travelled
97 of 135
Speed =
Distance/Time
98 of 135
Define acceleration
The rate of change of velocity
99 of 135
A resultant force can be shown using a what length arrow?
Longer
100 of 135
Force =
Mass * Acceleration
101 of 135
Braking distance + thinking distance =
Stopping distance
102 of 135
What is the unit for momentum?
Kg m/s
103 of 135
Initial K.E. = (in movement)
Work done by breaks to stop vehicle
104 of 135
True or false, energy transfers involve no losses?
False. Most transfers involve some losses, usually as heat or sound
105 of 135
Define isotope
Different forms of the same element with the same number of protons but different number of neutrons
106 of 135
What kind of process is radioactive decay?
Random and spontaneous
107 of 135
Is the mass number on the top or bottom?
Top
108 of 135
Is the atomic number on the bottom or top?
Bottom
109 of 135
How does an alpha particle cause ionisation?
It has a strong charge of +2 so it can PULL electrons out of orbit
110 of 135
How does beta radiation cause ionisation?
It has a negative charge of -1. There is a force of repulsion between the electrons so they PUSH it out
111 of 135
How do gamma rays cause ionisation?
It gives electrons energy to break free and become delocalised
112 of 135
What kind nucleus is an alpha particle?
Helium (He)
113 of 135
What blocks beta radiation?
Few cm of aluminium
114 of 135
How can fission generate electricity?
It released lots of KE (so also heat) which heats water in the boiler which generates steam which turns a turbine which turns the generator
115 of 135
What do moderators in the reactor do?
Slow the neutrons down so they can be absorbed by the uranium nuclei
116 of 135
What are control rods often made of?
Boron or graphite
117 of 135
How can a chain reaction happen in fission?
Each time a uranium nucleus splits, it spits out 2 or 3 neutrons which go on to split other uranium nuclei
118 of 135
Why does nuclear fusion have to happen at high temperatures?
To overcome the strong forces of electrostatic repulsion
119 of 135
Which produces more energy, fusion or fission?
Nuclear fusion
120 of 135
Why has the theory of cold fusion not been fully accepted yet?
MIT discredited the theory, hadn't been peer reviewed and not many other scientists can get the same results
121 of 135
Who were the two scientists that started the cold fusion theory?
Pons and Fleischmann
122 of 135
What % of the background radiation is radon gas?
51% (biggest)
123 of 135
Which factor accounts for less than 1% of the background radiation?
Nuclear industry
124 of 135
What % of the background radiation comes from cosmic rays?
10%
125 of 135
Which factors effecting background radiation levels are at 12%?
Medical and food
126 of 135
What are the factors effecting background radiation levels?
Radon gas, naturally occurring isotopes (rocks), medical, food, cosmic rays, nuclear industry
127 of 135
Define half life
The time it takes for half the undecayed nuclei to decay
128 of 135
A short half life means activity falls...
Quickly
129 of 135
Why do we have to use half lives?
The activity never reaches 0
130 of 135
What can be used to measure half life?
G-M tube
131 of 135
The severity of effects from radiation exposure depends on 2 things. What are they?
How much exposure. The energy (some are more penetrative than others)
132 of 135
Give 3 reasons nuclear waste is a massive problem in the UK?
Nuclear waste can't usually be recycled. Has a really long half life. Really dangerous
133 of 135
What are the advantages of nuclear power?
Doesn't burn fossil fuels. Uranium is cheap because it's abundant. Safer than people think
134 of 135
What are the cons of nuclear power?
Risk of leaks. Decommissioning of plants takes decades. People worry waste can never be properly and safely disposed of
135 of 135
Other cards in this set
Card 2
Front
Properties of beta radiation?
Back
Moderately ionising, quite fast, -1 charge, small mass, ejected electron, stopped by aluminium
Card 3
Front
Properties of gamma radiation?
Back
Card 4
Front
Properties of alpha radiation?
Back
Card 5
Front
Use of alpha radiation?
Back
Related discussions on The Student Room
- Physics Help »
- Messing up a paper »
- Ocr a physics 2023 grade boundaries »
- Predicted topics for physics P2 »
- Synoptic Question - Psychology AQA GCSE »
- Stats and mechanics »
- International gscs physics »
- aqa english lit - paper 1/2 confusion »
- Exam Dates A Levels 2024 »
- OCR A Level Law 2024 Predictions »
Similar Physics resources:
1.0 / 5 based on 2 ratings
1.0 / 5 based on 2 ratings
0.0 / 5
1.0 / 5 based on 2 ratings
1.0 / 5 based on 8 ratings
1.0 / 5 based on 1 rating
0.0 / 5
1.5 / 5 based on 8 ratings
1.0 / 5 based on 2 ratings
Comments
Report