Explain the difference between solid friction and viscosity.

Explain the difference between conductor and insulator.

What is a rigid body ? Explain the differences between rigid body and solid body.

Explain the difference between prism and pyramid.

Explain the difference between birds and mammals.

Explain the difference between conductor and semiconductor.

State the differences between solid, liquid and gas.

What is the difference between static friction and sliding friction ? For given pair of objects, which of the two is greater ?