Chapter 3 - Motion

Question 1

What is average velocity?

Answer 1

Average velocity is calculated by:

Average Velocity = displacement/time taken

v = ∆x / ∆t

Question 2

What properties can you derive from Distance-time graphs?

Answer 2

From a distance-time graph, you can find:

• The distance travelled on the y-axis.
• The time passed is on the x-axis.
• The speed over a time period is defined as the gradient of the line.

Question 3

How do you determine acceleration?

Answer 3

Average acceleration is determined:

acceleration = change in velocity/change in time

a = ∆v / ∆t

Question 4

What can you derive from velocity time graphs?

Answer 4

From velocity-time graphs, you can find:

• The velocity, on the y-axis.
• The time passed, on the x-axis.
• Acceleration, through the gradient of the curve.
• Displacement, through the area under the curve.

Question 5

What are the equations of motion?

Answer 5

The equations of motion are the SUVAT equations.

Question 6

What is the equation for thinking distance (the time taken for a driver to react to a need to stop?)

Answer 6

Thinking distance = speed x reaction time

Question 7

What are the rules for projectile motion?

Answer 7

For projectile motion, assuming no air resistance:

• Vertical velocity changes due to acceleration of free fall (g)
• Vertical displacement and time of flight can be calculated using equations of motion.
• Horizontal velocity remains constant.