Q. 215.0( 1 Vote )

# A cubical block of mass m and edge α slides down a rough inclined plane of inclination θ with a uniform speed. Find the torque of the normal force acting on the block about its centre.

Answer :

The torque on the sliding object is

Given

The mass of the cubical block is “m” and the edge size is given as “a” the plane is inclined at an angle with the block moving at a uniform speed.

Formula Used

The formula used is that of a torque which tells us the mechanics of force which helps the object to rotate. The formula is

where

F is the force applied on the object; r is the radius of the object turning. Turning angle is given by

Explanation

The block of mass “m” moves with a uniform velocity on an inclined plane of angle , the force applied on the block is

Now for the block not to roll the sum of the product of torque and force applied downwards and reactionary force due to the mass of the block should be zero

Hence, the torque on the sliding object is

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