CBSE Class 9 Physics Thrust Pressure Archimedes Principle Relative Density Worksheet

PHYSICS:

THRUST, PRESSURE, ARCHIMEDES PRINCIPLE, RELATIVE DENSITY

1. Explain:

  (a) Railway tracks are laid on large sized wooden or iron sleepers.

  (b) A sharp knife is more effective in cutting the object than a blunt knife.

  (c) A camel walks easily on a sandy surface than a man inspite of the fact that a camel is much heavier than a man.

  (d) A sharp needle pierces the wood easily but not a blunt knife although the force applied on both the needles is same.

2. A cubical block of mass 2 kg with each side of 2 cm is lying on ground. Calculate pressure exerted by block on ground.

3. The pressure exerted by weight of a cubical block of side 3 cm on surface is 5 Pa. calculate weight of the block. Force = weight.

4. Explain:

  (a) A bucket filled with water appears to be lighter inside the water.

  (b) A balloon filled with hydrogen rises up.

  (c) A small iron needle sinks in water but a ship made of iron floats in water.

  (d) A heavy stone can be lifted easily when immersed in water.

  (e) How does a submarine dives and then resurfaces above the water?

  (f) Explain the floating of ice-bergs in the sea water.

  (g) Why does the iron ball sink in the water but rubber ball floats in water?