The barometric reading at a place is 73.5m Hg. Calculate the pressure at a point 30m below the surface of water contained in a reservoir at the place. [g = 10ms\(^{-2}\), density of mercury = 1.2 x 10\(^4\)kg m\(^{-3}\), density of water = 1.0 x 10\(^3\)m\(^{-3}\)]
- 4.0 x 105 Nm-2
-
3.0 x 10 5 Nm-2
- 2.0 x 105 Nm-2
- 1.0 x 105 Nm-2
The correct answer is: B
Explanation
The pressure at a depth of 30 m below the surface is given by: p = h\(\rho\)g
P = 30 x 1000 x 10 = 3 x 10\(^5\)Nm\(^2\)