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प्रश्न
Explain various types of friction.
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उत्तर
There are two types of Friction:
(1) Static Friction:
Static friction is the force that opposes the initiation of motion of an object on the surface. The magnitude of static frictional force fs lies between
0 ≤ fs ≤ μsN
where, µs – coefficient of static friction
N – Normal force
(2) Kinetic friction:
The frictional force exerted by the surface when an object slides is called kinetic friction. Also called sliding friction or dynamic friction,
fk – µkN
where µk – the coefficient of kinetic friction
N – Normal force exerted by the surface on the object
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