Test Preparation on Motion in Two Dimension-II- Physics Test Series For NEET 2020

When a ceiling fan is switched off its angular velocity reduces
to 50% while it makes 36 rotations. How many more
rotation will it make before coming to rest (Assume uniform
angular retardation)

A stone of mass m is tied to a string and is moved in a
vertical circle of radius r making n revolutions per minute.
The total tension in the string when the stone is at its lowest
point is