A block of wood is kept on a table top The mass of the wooden block is 5 kg and its dimensions are `40cmxx20cmxx10cm`. Find the pressure exerted by the wooden block on the table top if it is made to lie on the table with its sides of dimension (a)`20cmxx10cm`(b) `40cmxx20cm`. Given`g=9.8(m)/(s^2)`.

A block of wood is kept on a table top The mass of the wooden block is

1.	A block of wood is kept on a table top The mass of the wooden block is 5 kg and its dimensions are `40cmxx20cmxx10cm`. Find the pressure exerted by the wooden block on the table top if it is made to lie on the table with its sides of dimension (a)`20cmxx10cm`(b) `40cmxx20cm`. Given`g=9.8(m)/(s^2)`.
Answer» the mass of the wooden block =5 kg the dimensions `=40 cm xx 20 cm xx 10 cm ` Here , the weight of the wooden block applies a thrust on the table top . that is Thrust `= F = mxxg` `=5 kg xx9.8 m s^(-2)` =49 N Area of side = length`xx` breadth `=20 cm xx 10 cm ` `=200 cm ^(2) = 0.02 m^(2)` From Eq .(10.20) Pressure `=(49)/( 0.02 m^(2)) ` `= 2450 N m^(-2)` when th block lies on its side of dimensions `40 cm xx20 cm ` it exerts the same throust Aera = length `xx` breadth `=40 cm xx20 cm` `=800 cm ^(2) = 0.08 m^(2)` From Eq .(10.20) , pressure `=(49) /(0.08 m^(2))` =612.5 ` N m^(-2)` the pressure ecerted by the side` 20 cm xx 10 cm ` is ` 2450 N m^(2) ` and by th side `40 cm xx 20cm ` is 612.5 `N m ^(-2)`