Question

Suzie (of mass 76 kg) is roller-blading down the sidewalk going 50 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 1.2 seconds. What is Suzie’s average acceleration?

Answer 1

Acceleration,
`a=-18.62\ m/s^2`

Step-by-step explanation:

Given that,

Mass of Suzie, m = 76 kg

Initial speed of Suzie, u = 50 mph = 22.35 m/s

Finally, it stops, v = 0

Time, t = 1.2 s

Let a is the Suzie’s average acceleration. It is equal to the rate of change of velocity. Its formula is given by :

`a=(v-u)/(t)`

`a=(0-22.35)/(1.2)`

`a=-18.62\ m/s^2`

So, the average acceleration of Suzie’s is
`18.62\ m/s^2` and she is decelerating. Hence, this is the required solution.