## Pages in this set

### Page 1

P2-1 : Motion
Speed and Velocity
The table below shows the distances travelled by a car over a given amount of time:

Distance (m) 0 1000 2000 3000 4000 5000 6000
Time (s) 0 40 80 120 160 200 240

We can represent this as a graph:

We call this…

### Page 2

Velocity is speed in a given direction. This means that if a moving object changes direction,
its velocity changes even if its speed stays the same. When the velocity changes, we say it
accelerates. Acceleration is calculated using the following equation:

Acceleration is generally measured in metres per second squared…

### Page 3

when a car hits a barrier it exerts a powerful force on the barrier, but the barrier
exerts a force in the opposite direction of an equal amount on the car
if you were to lay a book on a table, it exerts a force vertically down on the table,…

### Page 4

object falls, the greater the frictional force. Eventually, this would be equal to the weight of
the object ­ this resultant force is now zero, so the object will stop accelerating and begin
moving at a steady velocity ­ called the terminal velocity.

P2-3 : Work and Energy
Energy &…

### Page 5

momentum in one direction, and the gun recoils in the opposite direction with equal
movement.

When a force acts on a moving object (or an object which is able to move), its momentum
changes. The equation below describes this:

force = change in momentum ÷ time taken for change

N.B.…

### Page 6

When the same dry cloth is rubbed on the perspex rod, the electrons are transferred from
the rod onto the cloth.

Like charges repel and opposite charges attract, the bigger the distance between the forces,
the weaker the force.

When a charge flows through a conductor, there is a current…

### Page 7

P2-5 : Current Electricity
Electrical Circuits
Every circuit component has its own symbol. These are some of the main ones.

The symbols shown relate to their descriptions below. We use these symbols to make circuit
diagrams to show how components are connected to make a circuit.

A cell is necessary…

### Page 8

amps (A). The potential difference, or voltage, is measured using a voltmeter, which is
always placed in parallel with the component. The unit is a volt, V.

The graph shows a current-p.d. graph for a wire at a constant temperature. If the resistor is
kept at a constant temperature, the…

### Page 9

Power is measured in watts (W). Energy is measured in joules, J and time in seconds, s. In an
electric circuit, it is more common to measure the current and potential difference of a
device. We can also use current and p.d. to calculate the wattage:

Power = current x…

### Page 10

The two graphs above show the current-potential difference graphs for a filament lamp
(left) and a diode (right).

Series Circuits
In a series circuit, the components are connected one after the other, so if there is a break
anywhere, the current stops flowing. Because there is no choice about the…