Common fire extinguishers produce carbon dioxide by the action of sulphuric acid on sodium carbonate or sodium hydrogen carbonate. When the plunger is struck against a hard surface, the acid bottle breaks and a mixture of carbon dioxide and water gushes out of the nozzle. Do you think such a fire extinguisher would work if carbon dioxide were lighter than air?

Sand is often used to put out fires. How do you think this works?

Water should never be used to put out electrical fires. Can you guess why?

What are the things that might happen when a force is applied on a moving body?

Is magnetic force a contact force?

The pressure exerted by a liquid increases/decreases with depth.

Only the heavenly bodies exert a gravitational force on other bodies?

A manometer is used to measure _____.