Question

Force and pressure:In univ phy(young), ex 12.1 states weight(water)=1.3*10^5 lb which can collapse the floor. in Ex12.2, pressure(air)=4.6*10^5 lb [3.5 times more than weight(watre)]. But pressure(air) does not collapse floor coz it is balanced by same pressure underneath floor. If pressure(air) underneath floor is 3.5 times that of weight(water) acting on floor, then should it not prevent the floor collapse under water also? why does water alone collapse floor? press and force are different quantities but here force is normal and hence i think can be taken the same. can someone pls explain?

Answer 1

hint : Draw a fbd