Section 12: Forces Part 3

Question 1

What is a typical human reaction time?

Answer 1

0.25s

Question 2

Describe 2 ways of measuring reaction time

Answer 2

Dropping a ruler and catching it, computerised tests involving pressing a button in response to seeing something on the screen - time recorded by the computer

Question 3

What is stopping distance?

Answer 3

The total distance travelled by a car during the time between the driver seeing the hazard and the car coming to rest

Question 4

What is thinking distance?

Answer 4

The distance travelled by the car while the driver reacts to the hazard

Question 5

What is braking distance?

Answer 5

The distance travelled by the car while the brakes do work on the wheels to bring them to a stop

Question 6

What factors affect thinking distance?

Answer 6

Speed, alcohol, drugs, tiredness, distractions

Question 7

What factors affect stopping distance?

Answer 7

Speed, condition of the road, weather conditions, condition of tyres, condition of brakes

Question 8

What are the units of velocity?

Answer 8

m/s

metres per second

Question 9

What are the units of acceleration?

Answer 9

m/s²

metres per second per second

Question 10

What are the units of force?

Answer 10

N (newtons)

Question 11

What are the units of displacement?

Answer 11

m (metres)

Question 12

(HT) What are the units of momentum?

Answer 12

kg m/s (kilogram-metres per second)