A fan makes 10 revolutions in 3 second which is just switched on. Considering uniform acceleration the number of revolution made by the fan in next 3 seconds is

- 10
- 20
- 30
- 40

**Solutions:**

we have, where is the angular displacement and is the number of revolutions

from to , the fan made revolutions.

Applying equations of rotational motion:

Initial angular velocity So,

Now lets find the number of revolutions made from to . Applying the same equations of rotational motions as before:

using and We get,

number of revolution from to is 10

number of revolution from to is 40

hence, number of revolution made from to is (40-10) = 30

**Ans:** 30