A 0 .5 A_0.5 A 0 .5 kg block is held against a vertical rough wall. The coefficient of static friction is 0.2. Find the minimum horizontal force needed to keep the block at rest. Take g = 10 m s⁻².
Physics · Newtons law of motion and Friction · friction and single block problem
JEE Mains 2021

Question

A 0 .5 A_0.5 A 0 ​ .5 kg block is held against a vertical rough wall. The coefficient of static friction is 0.2. Find the minimum horizontal force needed to keep the block at rest. Take g = 10 m s⁻².

G1 Physics · Accepted Answer

Required upward friction is mg = 5 N. With horizontal push F, normal reaction N = F and maximum friction is μF = 0.2F. Setting 0.2F = 5 gives F = 25 N.

A 0 .5 A_0.5 A 0 ​ .5 kg block is held against a vertical rough wall. The coefficient of static friction is 0.2. Find the minimum horizontal force needed to keep the block at rest. Take g = 10 m s⁻².

A 0 .5 A_0.5 A 0 .5 kg block is held against a vertical rough wall. The coefficient of static friction is 0.2. Find the minimum horizontal force needed to keep the block at rest. Take g = 10 m s⁻².