Pages in this set

Page 1

Preview of page 1
PHYSICS UNIT 2 NOTES




Physics

RESULTANT FORCES

Forces work in pairs
The Resultant force is simply what you get when you add forces together
But you can only add forces which are opposite each other
Find the resultant force by finding the difference, of the numbers if they are opposite…

Page 2

Preview of page 2
PHYSICS UNIT 2 NOTES




Mass = a measure of how much stuff you are made up of (kg)
Weight = mass x gravitational field strength W=mg (N) = kg x (N/kg)
Earth's gravity = 10
Space's gravity = 0 (WEIGHTLESS)
Moon's gravity = 1.67
The faster the object, the greater…

Page 3

Preview of page 3
PHYSICS UNIT 2 NOTES




KE increases with greater mass and greater speed

KE= ½ x mass x speed2

When the height is zero there is no GPE, the KE is at a maximum

MOMENTUM

Momentum is a useful quantity to consider when thinking about `unstoppability'
Momentum (kg/s) = mass (kg)…

Page 4

Preview of page 4
PHYSICS UNIT 2 NOTES




If you rub two insulating materials together, electrons will transfer from one to another
One will become positively charged (the one with that lost electrons), the other will
become negatively charged (the one that gained electrons)
If something is neutral (not charged e.g. water) then it…

Page 5

Preview of page 5
PHYSICS UNIT 2 NOTES




The size of an electric current (I) = The number of electrons flowing (Q) / through a
component per second (t)
I = Q/t
Where
o I = Current in Amps
o Q = Charge in Coulombs
o t = Time

Words Symbols Units
Current I…

Page 6

Preview of page 6
PHYSICS UNIT 2 NOTES




The current through a resistance at a constant temperature is directly proportional to
the proportional difference (voltage) across the resistor.
Ohmic conductor = it's resistance is constant
If the temperature is not kept constant it will not be directly proportional = not
following Ohm's law

IV…

Page 7

Preview of page 7
PHYSICS UNIT 2 NOTES




If you remove or disconnect one component, the circuit is broken and everything in the
circuit stops. (This is why most Christmas lights are now connected in parallel circuits,
because if one bulb goes out they all go out. The only advantage of Christmas lights
connected…

Page 8

Preview of page 8
PHYSICS UNIT 2 NOTES




An AC = the current flows in one direction then back in the direction where it came from
(it is constantly changing direction back and forth)
A DC = the current flows in the same direction
The UK Mains supply an ALTERNATING CURRENT
Cells & Batteries…

Page 9

Preview of page 9
PHYSICS UNIT 2 NOTES




1
F requency (Hz) = Time Period (s)


The time period is the time it takes to make a complete wave (from peak to peak)
To find the time period measure the horizontal distance between the two peaks using the
divisions (the squares on the x…

Page 10

Preview of page 10
PHYSICS UNIT 2 NOTES




FUSES

We want an appliance which will blow if the current is too much ­ reason for fuse
Fuse protects the appliance so we know when the appliance is getting damaged
If the fuse rating is too high for the appliance it is letting the appliance…

Comments

No comments have yet been made

Similar Physics resources:

See all Physics resources »See all resources »