chapter 9 - motion

Question 1

distance VS displacement

Answer 1

• distance is a scalar quantity and only has a magnitude (size)
• displacement is a vector quantity and has both magnitude and direction

Question 2

speed VS 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

starting to move, stopping moving, speeding up, slowing down, and changing directions are examples of what?

Answer 3

acceleration / change in velocity

Question 4

what is acceleration?

Answer 4

change in velocity of an object per second

Question 5

what is the unit of acceleration?

Answer 5

m/s^2

Question 6

how does an object accelerate even when travelling at a steady speed?

Answer 6

if it is changing direction

Question 7

whats happening to an object when it has a negative acceleration?

Answer 7

it is slowing down

Question 8

what information does the gradient of the line in a distance-time graph provide?

Answer 8

speed

Question 9

what information does the gradient of the line in a velocity-time graph provide?

Answer 9

acceleration

Question 10

how can the distance travelled by an object be found from its velocity-time graph?

Answer 10

calculate the area under the graph

Question 11

equation linking speed, distance and time?

Answer 11

S = D/t
speed = distance / time

Question 12

equation linking velocity, displacement and time?

Answer 12

V = S/t
velocity = displacement / time

Question 13

characteristics of distance-time graphs?

Answer 13

• gradient is speed
• flat lines = stationary
• distanced travelled
• time taken
• displacement graphs tell directions

Question 14

characteristics of velocity-time graphs?

Answer 14

• gradient is acceleration
• area under graph is distance
• velocity at given time
• time taken
• curved line is non constant acceleration
• straight line is constant acceleration
• draw tangent to find acceleration of the curved line

Question 15

how do you work out change in velocity?

Answer 15

final - internal velocity

Question 16

S
u
V
a
t

Answer 16

S - displacement (m)
u - internal velocity (m/s)
V - final velocity (m/s)
a - acceleration (m/s^2)
t - time (s)