Question

solve this question

Answer 1

If the columns have to exert the same pressure (P) = F/A on the same area, they need to have the same F.

F will be the weight of the columns.

Now, we know

Density = Mass / Volume

Mass = Volume x Density

Now volume = area of base x Height = A x H

It is given that area is same

Mass = A x H x Density

Weight = M g

Now

Weight of water column = Weight of mercury column

A x Hwater x Densitywater x g = A x HMercury x DensityMercury x g

Hwater= HMercury x DensityMercury / Densitywater

= 70 cm x 13.6 g/cc / 1 = 952 cm

Answer 2

Let the rise in the mercury level in the other arm = h

Given, Density of mercury = 13.6 × 10^3 kg m^-3

Given, Density of water = 10^3 kg m^-3

The pressure exerted by both mercury and water should be same. pgh(water) = pgh(mercury).

13.6 * 10 ^3 * g = h * 13.6 * 10^3 * g

h = 1cm.

Hope this helps!