What is the principle behind a barometer?
A. The principle of buoyancy.
B. The principle of Bernoulli’s equation.
C. The principle of hydrostatic equilibrium.
D. The principle of gas law.
Answer:C
What is the principle behind a barometer?
A. The principle of buoyancy. B. The principle of Bernoulli’s equation. C. The principle of hydrostatic equilibrium. D. The principle of gas law.
Explanation: A barometer is an instrument used to measure atmospheric pressure. It operates on the principle of hydrostatic equilibrium, which states that the pressure at any point in a fluid at rest is the same in all directions. In a barometer, a column of mercury is used to measure atmospheric pressure. The weight of the mercury column is balanced by the atmospheric pressure, which causes the mercury level to rise or fall in the column.