GENERAL KNOWLEDGE

GK

PHYSICS

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
When seen from below, the blades of a ceiling fan are seen to be revolving anticlockwise and their speed is decreasing. Select correct statement about the directions of its angular velocity and angular acceleration.
A
Angular velocity upwards, angular acceleration downwards
B
Angular velocity downwards, angular acceleration upwards
C
Both angular velocity and angular acceleration upwards
D
Both angular velocity and angular acceleration downwards
Explanation: 

Detailed explanation-1: -The blades of a ceiling fan appear to be rotating anticlockwise and their speed is decreasing when viewed from below, indicating that angular velocity is operating downwards and angular acceleration is acting upwards.

Detailed explanation-2: -When seen from below, the blades of a ceiling fan are seen to be revolving anticlockwise and their speed is decreasing.

Detailed explanation-3: -the angular twist is to be so made that in which direction the fan rotor is rotating. at present the rotor is made rotate in the counterclockwise direction and the blades are made accordingly.

Detailed explanation-4: -Ceiling fans as a whole “rotate” on its axis, so we can say they are doing rotational motion, whereas fan blades move in a circle with a fixed radius from the centre; thus, they are doing circular motion.

Detailed explanation-5: -So, angular acceration of fan blades is 25 rad/sec2 in clockwise direction.

There is 1 question to complete.