Question

A block of wood is kept on a table top.The mass of wooden block is 5kg and it's dimensions are 40cm×20cm×10cm.Find the pressure exerted by the wooden block on the table top if it is made to lie of dimensions (a)20cm×10cm (b) 40cm×20cm

Answer 1

Mass of the wooden block = m= 5 kgdimensions = 40 cm × 20 cm × 10 cm
the weight of the wooden block applies a thrust on the table top.That is,Thrust = F = mg= 5 kg × 9.8 m/s²= 49 N

1)Area of a side = length × breadth
= 20 cm × 10 cm
= 200 cm²
= 0.02 m²

Pressure = thrust/ area
Pressure = 49 /0.02= 2450 N/m²

2)The same thrust in implied when it lies on the given dimension.
Area= length × breadth= 40 × 20= 800= 0.08 m²

Pressure = 49/0.08= 612.5