Question

Barometer which do not require any prior adjustment for reading atmospheric pressure is

• A. Aneroid barometer
• B. Fortin barometer
• C. Simple barometer
• D. All the above

Answer 1

The correct option is A Aneroid barometer

Aneroid barometers are popular for their light weight and size which increases its portability. The Aneroid barometer uses a small, flexible metal box called an aneroid cell (capsule). The evacuated capsule (or usually several capsules, stacked to add up their movements) is prevented from collapsing by a strong spring. Small changes in external air pressure cause the cell to expand or contract. This expansion and contraction drives mechanical levers such that the tiny movements of the capsule are amplified and displayed on the face of the aneroid barometer.

Since it is calibrated directly for the atmospheric pressure, no prior adjustments are required to be made before its usage.