CBSE
Multiple Choice QuestionsA body of mass 3 kg is acted on by a force which varies as shown in the graph. The momentum acquired is given by
zero
5 N-s
30 N-s
50 N-s
A gun of mass M fires a bullet of mass m with velocity v. Then, the recoil speed of the gun will be
n balls each of mass m impinge elastically each second on a surface with velocity v. The average force experienced by the surface will be
2nmv
nmv
4nmv
The minimum velocity (in ms-1) with which a car driver must traverse a flat curve of radius 150 m and coefficient of friction to avoid skidding is
60
30
15
25
A body of mass 5 kg moves on a straight path as a function of time x = t3 − 12t. The force on the body at t = 5s will be
100 N
150 N
120 N
130 N
The angle to which a cyclist bends when he covers a circular path of 34.3 m in s is
20°
30°
60°
45°
A string of negligible mass going over a clamped pulley of mass m supports a block of mass M as shown in the figure. The force on the pulley by the clamp is given by
If the coefficient of static friction between the tyres and road is 0.5, what is the shortest distance in which an automobile can be stopped when travelling at 72 kmh-1 ?
50 m
60 m
40.8 m
80.16 m
Two blocks of masses 2 kg and 5 kg are connected by an ideal string passing over a pulley. The block of mass 2 kg is free to slide on a surface inclined at an angle of 30° with the horizontal whereas 5 kg block hangs freely. The tension (T) in the string is
48.56 N
72.22 N
32.56 N
24.65 N
The upper half of an inclined plane with inclination is perfectly smooth, while the lower half is rough. A body starting from rest at the top will again come to rest at the bottom, if the coefficient of friction for the lower half is given by
2 sin
2 cos
2 tan
tan
