Question

Barometer was discovered by:
A) Fortin
B) Aneroid
C) Torricelli
D) None

Answer 1

Hint: Barometer is an instrument used to measure the atmospheric pressure. The pressure can be measured in different units. The units used to measure pressure are Torr, Pascal, and atmosphere. Among these units, Pascal (Pa) is the SI unit to measure the pressure.

Complete step by step answer:
(i) The barometer is an instrument used to measure the atmosphere. There are different types of barometers available now. But the first barometer was discovered by Evangelista Torricelli. Hence, in honouring him, the first unit to measure the pressure “Torr” was named after him.

$\therefore $ The barometer was discovered by Torricelli. Hence option (C) is correct.

Additional information:
i) When the air touches the ground, it experiences pressure. That pressure is called atmospheric pressure. The barometer is used to measure that pressure. The atmospheric pressure indicates the weather.
ii) The pressure is measured in Torr, Bar, Pascal, and atmospheres. For different applications, the pressure is measured in different units. In meteorology, the pressure of air is measuring in atmospheres.
iii) After the years, Torricelli had discovered the barometer $760mm$ of $Hg$ is regarded as the standard atmospheric pressure. To honour Torricelli, Torr was defined as the unit of pressure equal to the 1mm of Hg at $0^\circ C$.
iv) When scientists felt that the Torr was imprecise and varies by location. They defined the new unit, ‘atmosphere’ in 1954. The Torr was also then given new value with respect to the new unit atmosphere. Hence, One Torr is equal to the $\dfrac{1}{{760}}$ of one atmosphere.
v) The unit in honour of Torricelli was Torr. One Torr is equal to $\dfrac{1}{{760}}$of one atmosphere.

Note:
Aneroid is not the name of a person. It is the name of a barometer discovered by Torricelli. In 1800, Jean Nicholas Fortin invented the portable barometer. But the principle for the barometer was first given by Torricelli. And he discovered the first barometer.