Mercury is preferred as a barometric liquid because :

1. its density is high
2. its vapour pressure is negligible
3. it neither wets nor sticks to the glass
4. all of the above

Which of the following properties of water is incorrect regarding its non-usage as a barometric liquid?

1. It neither wets nor sticks to the glass tube
2. The vapour pressure of water is high
3. The surface of water cannot be easily seen while taking observations
4. The density of water is low.

The atmospheric pressure …………… with rising altitudes as the density of air …………… .

1. increases, decreases
2. decreases, increases
3. decreases, decreases
4. increases, increases

Altimeter is used in an aircraft to measure :

1. atmospheric pressure
2. altitudes
3. speed
4. distance travelled