Question

If the car’s speed decreases at a constant rate from 60 mi/hmi/h to 50 mi/hmi/h in 3.0 ss, what is the magnitude of its acceleration, assuming that it continues to move in a straight line?

Answer 1

Answer:

The magnitude of the acceleration is 1.2 × 10⁴ mi/h²

Explanation:

Hi there!

The acceleration is defined as the change in velocity in a time:

a = Δv / Δt

Where:

a = acceleration.

Δv = change in velocity  = final velocity - initial velocity.

Δt = elapsed time.

In this case:

Initial velocity = 60 mi/h

final velocity = 50 mi/h

elapsed time = 3.0 s

Let´s convert the time unit into h:

3.0 s · 1 h /3600 s = 1/1200 h

Now, let´s calculate the acceleration:

a = Δv / Δt

a = (50 mi/h - 60 mi/h) / 1/1200 h

a = -1.2 × 10⁴ mi/h²

The magnitude of the acceleration is 1.2 × 10⁴ mi/h²