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
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
1N
5 N
8 N
10N
A block of mass 2 kg rests on a rough inclined plane making an angle 300 with the horizontal. The coefficient of static friction between the block and the plane is 0.7. The frictional force on the block is
9.8 N
0.7×9.8 N
A block of mass 10 kg is placed on a rough horizontal surface whose coeffecient of friction is 0.5.If a horizontal force of 100 N is applied on it,then acceleration of block will be :
10 m/s2
5 m/s2
15 m/s2
0.5 m/s2
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 heavy uniform chain lies on horizontal table top.If the coeffecient of friction between the chain and the table surface is 0.25,then the maximum friction of the length of the chain that can hang over one edge of the table is
20 %
25 %
35 %
15 %
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
An iron block of sides 5 cm x 8 cm x 15 cm has to be pushed along the floor.The force required will be minimum when the surface in contact with ground is
8 cm x 15 cm surface
8 cm x 5 cm surface
5 cm x 15 cm surface
force is the same for all surfaces
If the normal force is doubled,then coefficient of friction is
halved
tripled
doubled
not changed
A block is lying static on the floor.The maximum value of static frictional force on the block is 10 N.If a horizontal force of 8 N is applied to the block,what will be the frictional force on the block ?
2 N
18N
8N
