# edexcel P2 topic 3

HideShow resource information
• Created by: bleona
• Created on: 06-12-12 19:32

First 138 words of the document:

TOPIC 3 ­ Motion and forces
Displacement, velocity, acceleration and force are vector quantities
(has a size and a direction).
Displacement is the distance travelled in a straight line.
Velocity is how fast an object is going at a particular direction.
m/s
Acceleration is how fast an objects velocity is changing. m/s s
Equation for speed =
Speed (metre per second, m/s) = distance (metre, m)/ time
(second, s)
Distance- time graph:
Straight horizontal line/ flat = stationary
(not moving)
Straight sloped line = steady speed
The steeper the line, the greater the
speed
Curve = acceleration (steepening) or deceleration(levelling off)
Velocity ­ time graphs:
Uphill straight line = acceleration
Downhill straight line = deceleration

## Other pages in this set

### Page 2

Here's a taster:

Curve = changing acceleration
The steeper the line, the greater the acceleration
Area under the graph = distance travelled
Acceleration is how quickly velocity is changing
This change in velocity can be a change in speed or direction or
both
Equation:
Acceleration (metre per second square, m/s s) = change in velocity
(metre per second, m/s)/ time (second, s)
(v-u) / (a x t) v = final velocity a = acceleration
U = initial velocity t = time
Forces
Arrows show the size and direction…read more

### Page 3

Here's a taster:

Resultant force (newton, N) = mass (kilogram, Kg) x acceleration
(metre per second square, m/s2)
Weight and mass:
Weight and mass are not the same.
Mass is a measure of how much stuff is in an object and it is
measured in kilograms, weight is a force measured in Newtons and
caused by the pull of gravity.
An object will have the same mass everywhere but its weight can

### Page 4

Here's a taster:

In space all objects accelerate at exactly the same rate. So on the
moon two things dropped will hit the ground together because
there is no air in vacuum therefore there is no air resistance to
slow down the object.
Newton's three laws of motion
1. A body will remain at rest (velocity of zero) or continue with
uniform (constant) motion unless a resultant force acts on it.
2. i) a body will accelerate if a resultant force is applied.…read more