Which of the following is the dimension of coefficient of friction?
[MLT-2]
[M0L0T0]
[M2LT-2]
[M2LT]
Two iron blocks of equal mass but with double surface area slide down an inclined plane with friction coefficient μ.If the first block with surface area A experience a frictional force f, then the second block with surface area 2A will experience a frictional force
f/2
f
2f
4f
A block of 10 kg is pulled at a constant speed on a rough horizontal surface by a force of 20 N.Find the co- effecient of kinetic friction .Given that g = 10 m/s2 .
0.2
0.5
0.85
0.7
A smooth block is released at rest on a 450 incline and then slides a distance d. The time taken to slide is n times as much to slide on rough incline than on a smooth incline. The coefficient of friction is
When a bicycle is in motion, the force of friction exerted by ground on the two wheels is such that, it acts
In the backward direction on the front wheel and in the forward direction on the rear wheel.
In the forward direction on the front wheel and in the backward direction on the rear wheel.
In the backward direction on both the front and the rear wheels.
In the forward direction on both the front and the rear wheels.
A block is kept on a frictionless inclined surface with angle of inclination α. The incline is given an acceleration a to keep the block stationary. Then a is equal to
g / tanα
g cosecα
g
g tanα
The upper half of an inclined plane of inclination θ is perfectly smooth while the lower is rough.A body starting from rest at the top comes back to rest at the bottom,if the coeffecient of friction for the lower half is given by
μ = sin θ
μ = cotθ
μ = 2 cosθ
μ = 2 tanθ
To avoid slipping while walking on ice one should take smallest steps because of the
larger friction
larger normal reaction
smaller friction
smaller normal reaction
Consider a car moving along a straight horizontal road with a speed of 72 km/hr.If the coeffecient of static friction between the tyres and the road is 0.5,the shortest distance in which the car can be stopped is
(Take g = 10 m/s2)
30 m
40 m
72 m
20 m
Three blocks of masses 2 kg, 3 kg and 5 kg are connected to each other with light string and are then placed on a frictionless surface as shown in figure. The system is pulled by a force F=10N, then tension T1 is
1 N
5 N
8 N
10 N
