(English Medium) ICSE Class 9 - CISCE Question Bank Solutions

Describe an experiment to demonstrate that air exerts pressure.

Explain the following :

A balloon collapses when air is removed from it.

Explain the following :

Water does not run out of a dropper unless its rubber bulb is pressed .

Explain the following :

Two holes are made in a completely filled sealed tin can to take out oil from it .

Why does the liquid rise in a syringe when its piston is pulled up?

How is water drawn up from a well by a water pump?

A partially inflated balloon is placed inside a bell jar connected to a vacuum pump. On creating vacuum inside the bell jar, balloon gets more inflated. How does the pressure change: increase, decrease or remains same, inside the (a) bell jar, (b) balloon?

What is the purpose of a barometer?

Explain how is the height of mercury column in tube of a simple barometer, a measure of the atmospheric pressure.

What is a barometer? 

Illustrate with the help of a labelled diagram of a simple barometer that the atmospheric pressure at a place is 76 cm of Hg.

Why is the barometric height used as unit to express the atmospheric pressure?

What is meant by the statement 'the atmospheric pressure at a place is 76 cm of Hg'? State its value in Pa.

How will you show that there is vacuum above the surface of mercury in a barometer? What name is given to this vacuum?

How is the barometric height of a simple barometer affected if  Its tube is pushed down into the trough of mercury?

How is the barometric height of a simple barometer affected if  Its tube is slightly tilted from vertical?

How is the barometric height of a simple barometer affected if A drop of liquid is inserted inside the tube?

State two uses of a barometer.

Give two reasons for use of mercury as a barometric liquid.

Give two reasons why water is not a suitable barometric liquid.