A-LEVEL Physics: 4.1.8: Graphs of Motion (Seneca)

Question 1

What is on Each Axis in Displacement-Time Graphs?

Answer 1

-x-axis: Time (s)

-y-axis: Displacement (m)

Question 2

If the Object is Not Acceleration (Travelling at Constant Velocity), what will the Graph be like?

Answer 2

The Graph will be a Straight Line.

Question 3

On a Displacement-Time Graph, what does the Gradient Represent?

Answer 3

Velocity.

Question 4

On a Displacement-Time Graph, y is the ___, & x is the ___. Hence, the Gradient (Change in y / Change in x) is the…

Answer 4

Displacement, Time, Velocity.

Question 5

Describe the Displacement-Time Graph for an Object that is Travelling at Constant Velocity (Not Accelerating).

Answer 5

Straight Line.

Question 6

Describe the Displacement-Time Graph for an Object Travelling Under Uniform (Constant) Acceleration. Why is this?

Answer 6

Line that Curves Upwards.
Because the Velocity (& therefore the Gradient) is Increasing (the Object is Under Constant Acceleration), so the Line Curves Upwards.

Question 7

The Larger the Acceleration, the ___ the Line in the Displacement-Time Graph ___ ___.

Answer 7

Faster, Curves Upwards.

Question 8

Describe the Displacement-Time Graph for an Object that is Decelerating.

Answer 8

Line that Curves Downwards.

Question 9

Describe the Displacement-Time Graph for an Object that is Stationary.

Answer 9

Horizontal Line.
The Gradient of the Graph = 0, as the Average Velocity of the Object is 0.

Question 10

How do you Find Instantaneous Velocity from a Displacement-Time Graph?

Answer 10

Draw a Tangent to the Curve at the Point if Interest, & Calculate its Gradient.
The Gradient of the Tangent is the Gradient of the Curve at that Point, & therefore = the Velocity at that Point in Time.

Question 11

How do you Find the Average Velocity from a Displacement-Time Graph?

Answer 11

Total Change in Displacement / Time Taken

Question 12

What is on Each Axis in a Velocity-Time Graph? (2)

Answer 12

-x-axis: Time (s)

-y-axis: Speed (ms-1)

Question 13

What is the ‘Gradient of a Line’?

Answer 13

The Gradient of a Line is the Change in y / the Change in x.

Question 14

What does the Gradient of a Velocity-Time Graph Represent? Why?

Answer 14

Acceleration. Because Gradient = y/x, which on a V-T graph is Change in Velocity / Time Taken = Acceleration.

Question 15

What does the Area Under a Velocity-Time Graph Represent?

Answer 15

The Displacement of the Object.

Question 16

What is on Each Axis in an Acceleration-Time Graph? (2)

Answer 16

-x-axis: Time (s)

-y-axis: Acceleration (ms-2)

Question 17

If the Acceleration-Time Graph is Positive, the Object is…

Answer 17

Accelerating.

Question 18

If the Acceleration-Time Graph is Negative, the Object is…

Answer 18

Decelerating.

Question 19

If the Acceleration-Time Graph is at Zero, there is No ___. What does this mean?

Answer 19

No Acceleration.
This Means that the Object is Stationary, or Moving at Constant Velocity.

Question 20

What does the Area Under the Acceleration-Time Graph Represent?

Answer 20

The Object’s Velocity.

Question 21

Any Line on an Acceleration-Time Graph that is Not Horizontal Indicates…

Answer 21

A Non-Uniform Acceleration.

Question 22

Any Line on an Acceleration-Time Graph that is Not Horizontal Indicates a Non-Uniform Acceleration. This Acceleration Can be…

Answer 22

Increasing or Decreasing.

Question 23

Decreasing Acceleration is Not the Same as Deceleration. Explain the Difference:

Answer 23

-Decreasing Acceleration is when the Rate of Acceleration Decreases.

-Deceleration is when the Object’s Speed Decreases.