P9- Motion

Question 1

What does the gradient of a line on a distance-time graph represent?

Answer 1

speed

Question 2

What unit is speed?

Answer 2

metres per second (m/s)

Question 3

what symbol is speed?

Answer 3

v

Question 4

What is distance traveled measured in?

Answer 4

metres

Question 5

What can the d/s*t equation be used to calculate?

Answer 5

the average speed of an object whose speed varies

Question 6

What should you do in the exam when time is given in minutes or hours in these calculations?

Answer 6

always convert it into seconds

Question 7

A steeper gradient equals to a?

Answer 7

faster speed

Question 8

What is velocity?

Answer 8

speed in a given direction

Question 9

An object that travels at constant velocity travels at what?

Answer 9

a constant speed without changing its direction (straight line)

Question 10

What is the word used for the distance travelled in a given direction?

Answer 10

displacement

Question 11

What is the acceleration of an object?

Answer 11

its change of velocity per second

Question 12

What is the unit of acceleration?

Answer 12

metre per second squared (m/s^2)

Question 13

Any object with a changing velocity is?

Answer 13

accelerating

Question 14

How can we work out average acceleration?

Answer 14

change in velocity/ time taken for the change

Question 15

How to find the change in velocity?

Answer 15

final velocity-initial velocity

Question 16

The equation of acceleration can be written as?

Answer 16

(final velocity - initial velocity)/ time taken for the change

Question 17

equation for acceleration as symbols?

Answer 17

a=(v-u)/t

Question 18

When is the term deceleration or negative acceleration used?

Answer 18

an object slows down

Question 19

When does a car decelerate?

Answer 19

when the driver brakes

Question 20

A minus value for acceleration means?

Answer 20

the object is slowing down

Question 21

How may you want to record how the velocity of an object changes?

Answer 21

-a motion sensor linked to a computer

Question 22

If you let a trolley accelerate down the runway, what happens?

Answer 22

its velocity increases wih time

Question 23

If the line is straight in the velocity time graph, what does this mean?

Answer 23

the increase in velocity was the same every second

-the acceleration of the trolley was constant

Question 24

What happens if you make the runway steeper for the trolley?

Answer 24

the trolely accelerates faster

Question 25

What would happen to the line on the velocity time graph if acceleration increases?

Answer 25

steeper gradient

Question 26

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

Answer 26

acceleration

Question 27

What does braking do?

Answer 27

reduces the velocity of a behicle

Question 28

What happens when a vehicle stops at a set of traffic lights?

Answer 28

the velocity is constant until the driver applies the brakes

Question 29

If the gradient of the velocity-time graph is zero, what does this mean?

Answer 29

acceleration in this section is zero

Question 30

When brakes are applied, what happens to the vehicle?

Answer 30

vehicle decelerates and its velocity decreases to zero

Question 31

What happens to the gradient of the line when brakes are applied?

Answer 31

the gradient of the line is negative | -acceleration is negative

Question 32

The area under the line on a velocity-time graph represents what?

Answer 32

the distance travelled in a given direction (or displacement)

Question 33

How can speed and velocity also be described in?

Answer 33

kilometres per hour (km/h)

Question 34

If speed and velocity are given in km/h, what must be done before plotting them on a graph or using them in?

Answer 34

their values must be converted to metres per second

Question 35

For an object moving at constant speed, what does the line in a distance-time graph look like?

Answer 35

a straight line sloping upwards

Question 36

What is the speed of the object is represented by?

Answer 36

the gradient of a line

Question 37

Why does the gradient represent acceleration?

Answer 37

change of velocity/time taken

Question 38

To find the distance travelled from the graph...

Answer 38

remember that the area under a line on a velocity-time graph represents the distance travelled

Question 39

What equation is useful for calculations where the time taken is not given and the acceleration is constant?

Answer 39

v^2 - u^2= 2as