Question

In the given figure, the height of a mercury barometer is 'h' cm when the atmospheric pressure is 101,000 Pa. Find the pressure at point X.

• A. 134.67 kPa
• B. 156.37 kPa
• C. 143.32 kPa
• D. 75.75 kPa

Answer 1

The correct option is D 75.75 kPa

As per figure, $P_{atm}$ = 101,000 Pa = h cm
Pressure at X will be equal = $P_x$ = ($h-\frac{h}{4}$) cm = $\frac{3h}{4}$ cm
Given, h = 101,000 Pa
$P_x$ = $\frac{3h}{4}$ = 101,000 Pa$\times \frac{3}{4}$
Or, $P_x$ = 75.75 kPa