In: Physics
A ceiling fan is turned on and reaches an angular speed of 120 rev/min in 50 sec. It is then turned off and coasts to a stop in 40 s. Find the total number of revolution made before the fan stops
Let us divide the problem in two parts, one before it reaches 120 rev/min in 50 sec and second during next 40 Second after it.
1.
Initial Angular Speed
Final Angular Speed
Then angular acceleration will be
Angular distance covered in this duration
2.
Initial Angular Speed
Final Angular Speed
Angular Acceleration will be
Angular distance covered in this duration
Total angular distance covered
Number of revolutions