Question

A block with length of 2.5 m, width of 1.2 m, height of 0.5 m and mass of 400 kg
lies on a table. What is the pressure at the bottom surface of the block?​

Answer 1

Given  :   Mass of iron block, m = 10 kg

               Acceleration due to gravity, g = 10 m/s2

so ,           weight of iron block, W  = m x g

                                                 = 10 x 10 = 100 N

So we can say force exerted by the iron block on the table top = 100 N

a ) 1st case -                    F = 100 N

                                 Area = 20 cm x 10 cm

                                        = 20 /100 m x 10 / 100 m

                                        = .02 m2

we know, Pressure = Force /Area

                          = 100 / .02 Pascal

                          = 5000 pa

b) 2nd case -                  F = 100 N

                                  Area = 10 cm x 5cm

                                        = 10 /100 m x 5/ 100 m

                                        = .005 m2

we know, Pressure = Force /Area

                          = 100 / .005 Pascal

                            = 20000 pa