Acceleration

Question 1

How is acceleration different from velocity or speed?

Answer 1

Acceleration is the change in velocity over a certain amount of time

Question 2

What is the formula for calculating the average acceleration of an object?

Answer 2

Question 3

What is deceleration, and how does it relate to acceleration

Answer 3

Deceleration is simply negative acceleration, occurring when something slows down, resulting in a negative change in velocity

Question 4

A car is travelling along a road when it collides with a tree and comes to a stop. Estimate the deceleration of the car:

Answer 4

1) First, give a sensible speed for the car to be travelling at (this should be memorised as 25m/s)
2) Next, estimate how long it would take the car to stop.
3) Put these numbers into the acceleration equation(as it came to a stop the change in velocity would be 0-25)
4)The question asked for the deceleration, so you can use the minus sign to show the car is losing down

Question 5

What is another name for constant acceleration?

Answer 5

Uniform acceleration

Question 6

What is acceleration due to gravity, and what is its typical value near the Earth’s surface?

Answer 6

-It is approximately 9.8 m/s^2 near the Earth’s surface
-it is equivalent to gravitational field strength and would be the acceleration of anything that is dropped

Question 7

What equation can be used for uniform acceleration?

Answer 7

Final velocity^2 (m/s)-initial velocity^2(m/s)=2 x acceleration(m/s^2) x distance (m)

Question 8

A van travelling at 23m/s starts decelerating uniformly at 2.0m/s^2 as it heads towards a built up area 112m away. What will its speed be when it reaches the built up area?

Answer 8

1) First, rearrange the equation so v is on one side.
2) Now put the numbers in - remember a is negative because it’s a deceleration.
3)Finally, square root the whole thing.