Question

A flywheel flows from 250rpm to 150rpm in 4.2 seconds. How many revolutions occur during this time ​

Answer 1

Answer:

7revolutions

Explanation:

Given parameters:

Initial revolution  = 250rpm

Final revolution  = 150rpm

Time  = 4.2s

Unknown:

Number of revolutions that occur at this time = ?

Solution:

To solve this problem;

 let us find the change in revolution  = 250rpm - 150rpm  = 100rpm

Convert the time to seconds;

         60s makes 1 minute

        4.2s will make $\frac{4.2}{60}$   = 0.07min

So;

      The number of revolutions at this time  = 100rpm x 0.07min

         =   7revolutions