1

### IIT-JEE 1994

A block of mass 0.1 is held against a wall applying a horizontal force of 5 N on the block. If the coefficient of friction between the block and the wall is 0.5, the magnitude of the frictional force acting on the block is:
A
2.5 N
B
0.98 N
C
4.9 N
D
0.49 N
2

### IIT-JEE 1980

A block of mass 2 kg rests on a rough inclined plane making an angle of $30^\circ$ with the horizontal. The coefficient of static friction between the block and the plane is 0.7. The frictional force on the block is
A
9.8 N
B
0.7$\times$9.8$\times $$\sqrt 3 N C 9.8 \times$$\sqrt 3$ N
D
0.7$\times$9.8
3

### IIT-JEE 1980

A ship of mass 3 $\times$ 107 kg initially at rest, is pulled by a force of 5 $\times$ 104 N through a distance of 3 m. Assuming that the resistance due to water is negligible, the speed of the ship is
A
1.5 m/s
B
60 m/s
C
0.1 m/s
D
5 m/s