P9 Motion

Question 1

How do you find the speed from a distance-time graph if the object is accelerating?

Answer 1

Draw a tangent to the curve and find the gradient.

Question 2

What is the difference between speed and velocity?

Answer 2

speed is a scalar quantity and only has a magnitude (size), velocity is a vector quantity and has both magnitude and direction

Question 3

What factors can affect the speed at which someone walks, runs, or cycles?

Answer 3

age, fitness, terrain, and distance travelled

Question 4

What are typical speeds for a person walking,
running, and cycling?

Answer 4

1.5m/s, 3.0m/s, and 6.0m/s respectively

Question 5

What are typical speeds of a car and a train?

Answer 5

13–30m/s and 50m/s respectively

Question 6

What is a typical speed for sound travelling in air?

Answer 6

330m/s

Question 7

What is acceleration?

Answer 7

change in velocity of an object per second

Question 8

What is the unit of acceleration?

Answer 8

m/s2 (squared)

Question 9

How can an object be accelerating even if it is travelling at a steady speed?

Answer 9

if it is changing direction

Question 10

What is happening to an object if it has a negative
acceleration?

Answer 10

it is slowing down

Question 11

What information does the gradient of the line in a distance–time graph provide?

Answer 11

speed

Question 12

What information does the gradient of the line in a velocity–time graph provide?

Answer 12

acceleration

Question 13

How can the distance travelled by an object be found from its velocity–time graph?

Answer 13

calculate the area under the graph