Friction can cause noise in machines.

Choose the right word: (streamlined, round)

This shape helps aeroplanes to move at a very high speed.

Choose the right word: (rough, smooth)

These surfaces have less friction.

Choose the right word: (gravitational, contact)

The force exerted when one object comes in contact with another: _____ force.

These are used to reduce noise in machines.

Friction acts in this direction to that of the motion of an object.

Complete the concept map.