Distance, speed, velocity and acceleration

Question 1

Speed, Distance and Time

Answer 1

D= S x T
Speed measured in ms-1

Question 2

Acceleration (Deceleration)
Meausred in ms-2

Answer 2

Change in velocity / Time

Question 3

Velocity

Answer 3

Speed of an object (m/s) but in a particular direction
To calculate it use displacement travelled (direct distance) rather than the actual distance

Question 4

Distance time graphs

Answer 4

Straight line across graph = Stationary (not moving)
Increasing line = Constant speed (forwards)
Decreasing line = Constant speed (back to start)

Steeper slope = faster velocity
Velocity = slope of graph = height/base

Question 5

Velocity time graphs

Answer 5

Straight rising line = Acceleration
Straight falling line = Decceleration
Horizontal line= Constant speed

Accelartion = slope of graph = height/base
Distance travelled = area under graph

Question 6

Stopping distance

Answer 6

Road accidents happen because people often underestimate the distance needed to slow a car until it stops
Stopping distance=Thinking distance+Braking distance

Question 7

Cars braking distance

Answer 7

Thinking distance- Distance travelled whilst reacting
Braking distance- Distance travelled whilst braking

Question 8

Reaction time

Answer 8

Thinking distance= Speed x reaction time

Question 9

Factors affecting thinking, braking and stopping distances

Answer 9

Thinking distance Braking distance
Age of driver Wet and icy roads
Alcohol and drug use Brakes in bad condition
Speed Poor tyres
Speed

Question 10

Ways to reduce the speed of a driver

Answer 10

Speed cameras, speeding fines and black boxes