When a Fortins barometer is used to measure the pressure on the surface of the earth and on the top of a building the main scale redaing is found to be the same and the vernier scale reading is found to be 9 and zero, respectively. If one M.S.D. is 1 mm and number of vernier scale divisions is 10, calculate the height of the building. Take the average density of air as `1.3 kg m^(-3)`, and that of mercury as `13.6 g cm^(-3)`

Explanation

When wind blows with high speed over the roof of a hut, the roofis blown away due to the pnssure difference created between top and bottom surfaces of the roof. Hence, R is not the correct explanation of A.