A man of mass 40 kg is at rest between the walls as shown in the figure. If 'µ' between the man and the walls is 0.8, find the normal reaction exerted by the walls on the man. (g=10ms–2)
If N be the normal reaction of each wall, then total frictional force = 2(µN) 2(µN) = mg
N = 250 newtons.