A particle of mass m is suspended from a ceiling through a massless string. The particle moves in a horizontal circle as shown in the given figure. The tension in the string is:
1. mg
2. 2mg
3. 3mg
4. 4mg
A particle of mass m is attached to a string and is moving in a vertical circle. Tension in the string when the particle is at its highest and lowest point is respectively. Here is equal to:
1. | mg | 2. | 2mg |
3. | 4mg | 4. | 6mg |
Choose the incorrect alternative:
1. | Newton's first law is the law of inertia. |
2. | Newton's first law states that if the net force on a system is zero, the acceleration of any particle of the system is not zero. |
3. | Action and reaction act simultaneously. |
4. | The area under the force-time graph is equal to the change in momentum. |
A block slides down on a 45° rough incline in thrice the time it takes to slide down on a frictionless 45° incline of the same length. The coefficient of friction between the block and the rough incline is:
1. | 0.6 | 2. | 0.7 |
3. | 0.5 | 4. | 0.9 |
The kinetic energy 'K' of a particle moving in a circular path varies with the distance covered S as K = a, where a is constant. The angle between the tangential force and the net force acting on the particle is: (R is the radius of the circular path)
1.
2.
3.
4.
The tension in the string connecting blocks, B and C, placed on a smooth horizontal surface in the following diagram is:
1. | 25 N | 2. | 30 N |
3. | 32.5 N | 4. | 37.5 N |
If two forces ( ) and ( ) N are acting on a body of mass 2 kg, then the acceleration produced in the body in will be:
1. ( )
2. ( )
3. ( )
4. ( )
The friction between the front foot and the back foot when walking on a horizontal surface is, respectively:
1. Forward, forward
2. Backward, backward
3. Forward, backward
4. Backward, forward
A simple pendulum hangs from the roof of a train moving on horizontal rails. If the string is inclined towards the front of the train, then the train is:
1. moving with constant velocity.
2. in accelerated motion.
3. in retarded motion.
4. at rest.
A block of mass M is pulled by a force F, making an angle with the horizontal on a smooth horizontal surface as shown. If a is the acceleration of block on the surface, then the contact force between the block and the surface will be:
1. Mg + Macos
2. Mg - Macos
3. Mg + Matan
4. Mg - Matan