Physics
Friction is increased if :
- an oil is sprayed
- the surfaces are made wet
- the surfaces are made dry
- the surfaces are polished
Force
6 Likes
Answer
the surfaces are made dry
Reason — Friction can be increased by the following three ways :
- By making the surfaces rough
- By using dry surfaces
- By increasing the weight
Answered By
3 Likes
Related Questions
Friction is reduced by :
- making the surfaces wet
- making the surfaces dry
- making the surfaces rough
- sprinkling sand on the surface.
Friction :
- causes wear and tear
- produces heat
- stops a moving body
- has all the above disadvantages
Fill in the blanks :
(a) Force is applied as …………… or …………… .
(b) On squeezing a gum tube, its …………… changes.
(c) On pulling a string, its …………… increases.
(d) A moving football when kicked, its …………… changes.
(e) On applying brakes on a moving car, its speed …………… .
(f) We use ball bearings to …………… the friction.
(g) Friction …………… motion.
(h) Lubricants are used to …………… friction.
(i) Friction causes …………… of moving parts of a machine.
Write true or false for each statement :
(a) The frictional force acts in the direction of motion of body.
(b) The unit of weight is kilogram.
(c) A force can change the direction of motion of a moving body.
(d) A force increases the mass of the body when applied on it.
(e) The force of friction is always disadvantageous.
(f) The sliding friction is more than the rolling friction.
(g) Liquids offer more friction than the gases.
(h) A wet oily road offers more friction than a dry rough road.