Question

Let's say you are driving at 55 mph and run up

behind a car and have to slow down to 40 mph in
4 seconds. What is your acceleration?

Answer 1

See below

Step-by-step explanation:

Acceleration = Δv / Δt

= (40-55) / 4 s = - 3.75 miles per hour per second

here is the same answer with different units

-15 mi/hr = -22 f/s

-22 ft / s / 4s = -5.5 ft/s^2