If the coefficient of friction of a surface of , then the angle of inclination of the plane to make a body on it just to slide is
300
600
450
900
A block has been placed on an inclined plane with the slope angle θ, block slides down the plane at constant speed. The coefficient of kinetic friction is equal to
sinθ
cosθ
g
tanθ
A body of mass 10 kg falls vertically on a muddy ground with a velocity of 20 m/s and penetrates through a vertical depth of 0.3 m.Calculate the average force exerted by the muddy ground?Take g = 10 m/s2 .
6767 N
7894 N
7845 N
5894 N
What should be the tension in a rope pulling vertically upward a mass of 100 kg so that starting from rest it acquires a velocity of 4 m/s in 1.5 seconds?
1278 N
1247 N
1287 N
1894 N
The mass of a ship is 2×107 kg. On applying a force of 25×105N, it is displaced through 25 m. The speed of ship is
2.5 m/s
5 m/s
3.7 m/s
12.5 m/s
A 600 kg rocket is set for a vertical firing.If the exhaust speed is 1000 m/s,the mass of the gas ejected per second to supply the thrust needed to overcome the weight of rocket is
117.6 kgs-1
58.6 kgs-1
6 kgs-1
76.4 kgs-1
A block of mass 50 kg just slides over a horizontal distance of 1 m. If coefficient of friction between their surfaces is 0.2, the work done against friction is
98 J
56 J
72 J
34 J
A cricket player catches a ball of mass 100g and moving with a velocity of 25ms-1. If the ball is caught in 0.1s, the force of the blow exerted on the hand of the player is
4N
25N
40N
250N
A man fires a bullet of mass 200 g at a speed of 5 m/s. The gun is of one kg mass. By what velocity the gun rebounds backward?
1 m/s
0.01 m/s
0.1 m/s
10 m/s
Two masses as shown in the figure are suspended from a massless pulley. The acceleration of the system when masses are left free is