Tue July 17, 2012 By:

A block of mass 0.1 kg is held against a wall by applying a horizontal force of 5N on the block.If the coefficient offriction between the block and the wall is 0.5 ,find thwe magnitude of frictional force acting on the block.

Expert Reply
Tue July 17, 2012
The diagram can be shown as:
Frictional force will be directed upwards as shown as gravity will be assisting its motion and the frictional force will be due to 5 N force normal to the block towards the wall.
Hence max. static frictional force: F = 0.5 x 5 = 2.5 N
FOrce due to mass of block= mg = 0.1 x 10 = 1 N
Since it is less than max static frictional force hence frictional force on the block will be 1 N
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