Measures to reduce friction:
1. Grease, oil, graphite etc. are used as lubricants in machines to reduce friction.
2. Ball bearings and roller bearing are used in vehicles and machines to reduce friction.
3. Oil is used to reduce friction in engines.
4. Powder is sprinkled on the board while playing carrom.
5. Vehicles are shaped keeping aerodynamics in mind so that friction with air can be reduced.