Suzie (of mass 58 kg) is roller-blading down

Question

the sidewalk going 36 miles per hour. She
notices a group of workers down the walkway
who have unexpectedly blocked her path, and
she makes a quick stop in 2
.
4 seconds.
What is Suzie’s average acceleration?

Answer 1

Put the 36mph into m/s units.

acceleration(final speed-oritinal speed)/time

final speed is zero.