calculate the largest and least pressure exerted by a metal block of size 20*8*5cm and having a mass of 5kg
Given: Mass of the block = 5 kg, Force exerted by the block = mg = 49.05 kg
Dimensions of the block, l×b×h = 20×8×5 cm or 0.2×0.08×0.05 m
Now
Pressure = Force/Area, Area of contact with the surface on the pressure is being exerted
Since we can place the cuboid in a no of ways on the surface so For minimum pressure we keep it along its length to get the maximum surface of contact and along its width for minimum surface of contact to get maximum pressure, and since every face of a cuboid is a rectangle itself,
∴ minimum pressure = 49.05/( l×b )
= 49.05/0.016 = 3065.625 Nm-2
similarly for maximum pressure = 49.05/( b×h )
= 49.05/0.004 = 12262.5 Nm-2