Advertisements
Advertisements
प्रश्न
State the empirical laws of static and kinetic friction.
Advertisements
उत्तर
The empirical laws of friction are:
- Friction is independent of the surface of contact.
- The coefficient of kinetic friction is less than the coefficient of static friction.
- The direction of frictional force is always opposite to the motion of one body over the other.
- Frictional force always acts on the object parallel to the surface on which the object is placed,
- The magnitude of frictional force between any two bodies in contact is directly proportional to the normal reaction between them.
APPEARS IN
संबंधित प्रश्न
An object of mass m begins to move on the plane inclined at an angle θ. The coefficient of static friction of inclined surfaces is µs. The maximum static friction experienced by the mass is ______
People often say “For every action, there is an equivalent opposite reaction”. Here they meant ‘action of a human’. Is it correct to apply Newton’s third law to human actions? What is mean by ‘action’ in Newton's third law? Give your arguments based on Newton’s laws.
Briefly explain the origin of friction. Show that in an inclined plane, the angle of friction is equal to the angle of repose.
A block of mass 20 kg is sliding on a surface is inclined at an angle of 45° with the horizontal. What will be the acceleration of the block if the coefficient of kinetic friction between the block and the surface is 0.7?
A block of mass m slides along a floor while a force of magnitude F is applied to it at an angle θ as shown in figure. The coefficient of kinetic friction is µK. Then, the block's acceleration 'a' is given by ______.
(g is acceleration due to gravity)
If a body of mass m is moving on a rough horizontal surface of coefficient of kinetic friction µ, the net resultant force exerted by surface on the body is ______.
Block A has a mass of 2 kg and block B has 20 kg. If the coefficient of kinetic friction between block B and the horizontal surface is 0.1, and B is accelerating towards the right with a = 2 m/s2, then the mass of the block C will be ______.
(g = 10 m/s2)
A chain of mass 'M' and length 'L' is put on a rough horizontal surface and is pulled by constant horizontal force 'F' as shown in the figure. The velocity of the chain as it turns completely ______.
(Coefficient of friction = μ)
A body starts from rest on a long inclined plane of slope 45°. The coefficient of friction between the body and the plane varies as µ = 0.3 x, where x is distance travelled down the plane. The body will have maximum speed (for g = 10 m/s2) when x = ______.
There are two inclined surfaces of equal length (L) and same angle of inclination 45° with the horizontal. One of them is rough and the other is perfectly smooth. A given body takes 2 times as much time to slide down, on rough surface than on the smooth surface. The coefficient of kinetic friction (μ) between the object and the rough surface is close to ______.
