section 1 - forces and motion Flashcards
1
Q
what is the equation for average speed?
A
average speed = distance moved / time taken
2
Q
what is the equation for acceleration?
A
acceleration = change in velocity / time taken
3
Q
what is the equation for v2?
A
v2 = u2 + 2as
4
Q
distance - time graphs
A
- the gradient gives the speed of the object
- flat sections are where it has stopped
- a steeper graph means its going faster
- curves represent acceleration
- a curve getting steeper means it is speeding up
- a levelling off curve means its slowing down
5
Q
velocity - time graphs
A
- gradient = acceleration
- flat sections represent steady speed
- the steeper the graph, the greater the acceleration or deceleration
- uphill sections are acceleration
- downhill sections are deceleration
- a curve means changing acceleration
- the area under any part of the graph is equal to the distance travelled in that time interval
6
Q
what is the gravity on earth?
A
10 m/s2
7
Q
what is weight measured in?
A
newtons, N
8
Q
what do you use to measure weight?
A
newton meter
9
Q
what is mass measured in?
A
kg
10
Q
what do you use to measure mass?
A
mass balance
11
Q
what is the equation for weight?
A
weight = mass x gravitational field strength
12
Q
what are the different types of force?
A
- gravity or weight
- reaction force
- electrostatic force
- thrust
drag or air resistance or friction - lift
- tension
13
Q
what is the equation for momentum?
A
momentum = mass x velocity
14
Q
What 3 main ways does friction occur?
A
- Friction between solid surfaces which are gripping
- Friction between solid surfaces which are sliding past each other
- Resistances or drag from fluids (liquids or gas in air)
15
Q
What is the differences between distance and displacement?
A
- distance is a scale quantity - it only has a magnitude.
- displacement is a vector quantity - it has magnitude and direction.
