Answer:
The distance used to calculate the pressure of atmosphere is 75 cm.
Explanation:
- Mercury barometer is used to find the pressure of the atmosphere where it is placed.
- As shown in the figure, the barometer has an inverted tube where mercury has risen by 75 cm. This height is taken into count to measure the atmospheric pressure.
- At the place with high pressure the mercury in the inverted tube will go very high and vice versa.
- Hence to find the pressure we must note down the height of mercury that has risen the inverted tube.