Question

This should be the format of your answer:

Ex. Given: distance = 500 m/s
time = 10 s
Asked: speed
Formula: d/t
Solution: 500 m/10 s
Answer: 50 m/s

2. The new Ferrari can accelerate from rest to 100 km/hr in 5 seconds. What is the average acceleration of the car in m/s2?
3. A car starts from a stoplight and is traveling with a velocity of 10 m/sec east in 20 seconds. What is the acceleration of the car?
4. A ball is rolled at a velocity of 12 m/s. After 36 seconds, it comes to a stop. What is the acceleration of the ball?

Answer 1

The answer is below

Explanation:

Acceleration is the time rate of change in velocity. Acceleration is given by:

Acceleration = change in velocity / time taken

Acceleration = (final velocity - initial velocity) / time

1) The Ferrari is from rest, hence initial velocity = 0. The final velocity = 100 km/h =
`(100\ km*1000\ (m)/(km) )/(1\ hr*(3600\ s)/(1\ hr) ) =27.78\ m/s`, time = 5 s

Acceleration = (0 - 27.78) / 5 = 5.56 m/s²

2) The car has initial velocity = 10 m/s. The final velocity = 10 m/s since velocity is constant. time = 20 s

Acceleration = (10 - 10) / 20 = 0 m/s²

3) The ball has initial velocity = 12 m/s. The final velocity = 0 m/s since it stops. time = 36 s

Acceleration = (0 - 12) / 36 = -0.33 m/s²