Force and Press...

A When does a body float on water?

In which of the following cases the net force is NOT equal to zero?

We use a straw (narrow pipe) to drink juice from a glass. What make this possible?

Which of the following effects is NOT caused by the magnetic force between a magnet and a magnetic substance?

 In cities, water from an overhead tank is supplied to houses using the principle of

(i) difference in pressure.

(ii) gravitational force.

(iii) decrease of friction m pipes.

A deep sea diver's ears get hurt when he is inside the water. What is the cause for it?

What does a barometer measure?

Four forces are acting on a body. If the body does not change its position or shape/then what does it mean?

Why do deep sea divers use a special suit for diving?

On what factors does the magnitude of non-contact force depend?