3.1 Motion

Question 1

How is speed calculated?

Answer 1

Distance / time

Question 2

How is velocity calculated?

Answer 2

Displacement / time

Question 3

How is acceleration calculated?

Answer 3

(v - u) / t

Question 4

How is average speed calculated from a distance-time graph?

Answer 4

The gradient of a straight line drawn from the lowest to the highest point of the curve

Question 5

How is instantaneous speed calculated from a distance-time graph?

Answer 5

Tangent drawn to the curve at a given point

Question 6

What does the gradient of a displacement-time graph represent?

Answer 6

Velocity

Question 7

What is acceleration?

Answer 7

The rate of change of velocity

Question 8

What does negative acceleration mean? (2)

Answer 8

Slowing down

Acceleration in the opposite direction

Question 9

What does the gradient of a velocity-time graph represent?

Answer 9

Acceleration

Question 10

What does the area beneath a velocity-time graph represent?

Answer 10

Displacement

Question 11

What is stopping distance? (2)

Answer 11

The total distance travelled before stopping

Thinking + braking

Question 12

What is thinking distance? (2)

Answer 12

The distance travelled as the driver reacts

Uses s = d/t

Question 13

What is braking distance? (2)

Answer 13

The distance travelled whilst braking

Uses suvat

Question 14

What factors affect thinking distance? (5)

Answer 14

Age
Drugs
Visibility
Distractions 
Alcohol

Question 15

What factors affect braking distance? (5)

Answer 15

Brakes
Grip of tyres 
Quality of car
Weather
Surface of the road

Question 16

What factor affects stopping distance?

Answer 16

Speed

Question 17

What is a projectile? (2)

Answer 17

An object that only experiences a force due to gravity and experiences no effects from other forces
Its motion can be split into vertical and horizontal components

Question 18

What happens to the horizontal component of velocity as an object free falls?

Answer 18

There are no resistive forces so velocity is constant

Question 19

What happens to the vertical component of velocity as an object free falls?

Answer 19

The object is only affected by gravity so it has acceleration of 9.81 ms^-2

Question 20

What is parabolic motion?

Answer 20

The path traced by an object with just vertical acceleration and constant horizontal velocity

Question 21

What was Aristotle’s view of motion? (2)

Answer 21

Natural motion - what an object naturally wants to do

Violent motion - what an object has to be forced to do

Question 22

What was Galileo’s view of motion? (2)

Answer 22

He realised that the classic view of motion did not recognise the role of friction in slowing objects down
In the absence of friction, objects will move freely