Obtain a pillow made of foam rubber. Press
down hard with your two hands on the surface
of the pillow. Then withdraw your hands
Describe what happened to its shape while you
pushed hard on the pillow and when you
withdrew your pushing. Repeat this activity on
a piece of rectangular block of wood and a
plasticine. Note the different effects.

The pillow is made up of foam rubber which can be compressed easily due to the soft compressible rubber with hands on application of pressure on the surface. The shape of pillow regain its original shape when the pressure is withdrawn from the pillow. If the same activity is performed on the piece of rectangular block of wood and plasticine. Then the rectangular block of wood cannot be compressed with hand as it is a solid body. Plasticine is a putty like material. It is a clay like material and it can be compressed with hand but when the pressure is withdrawn the plasticine does not regain its shape back.