Correct Answer - Option 3 : Dead weight pressure gauge
A pressure gauge is a mechanical instrument designed to measure the internal pressure and vacuum of a system.
Types of pressure gauge:
Dead weight pressure gauge: It uses known traceable weights to apply pressure to a fluid to check the accuracy of readings from other pressure measuring gauges. A deadweight pressure gauge is used for calibration of the other pressure measuring gauges
Bourdon tube pressure gauges: These are the most common type and are used to measure medium to the high pressure of both gaseous and liquid fluids. Pressure measured by it ranges from 0.6 bar to 7000 bar.
Diaphragm pressure gauge: These are used for relative pressure as well as vacuum, compound, and differential pressure applications in the pressure range of 10 mbar to 40 bar.