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A ladder AB supported by a smooth vertic...

A ladder AB supported by a smooth vertical wall and rough horizontal floor as shown. A boy starts moving from A to B slowly. The ladder remains at rest. Pick up the correct statement(s).

A

Magnitude of normal reaction by wall on ladder will increase

B

magnitude of normal reaction by wall on ladder will decrease

C

magnitude of normal reaction by floor on ladder will remain unchanged

D

magnitude of friction force by floor on ladder at will increase.

Text Solution

Verified by Experts

The correct Answer is:
A, C, D
Let m and `M` be mass of man and ladder. From FBD normal reaction at `A` is `N_(1)=(m+M)g` which remains constant net
Torwue on man `+` ladder is zero about B. if x decreases then torque of mg about B will decrease. Hence `f` must increase
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