JEE Physics Online Test Work Energy And Power Set C

1. A bullet weighing 10 g and moving with a velocity 300 m/s strikes a 5 kg block of ice and drop dead. The ice block is kept on smooth surface. The speed of the block after the collision is

2. A ball is allowed to fall from a height of 10 m. If there is 40% loss of energy due to impact, then after one impact ball will go up by

3. A bullet of mass m moving with velocity v strikes a suspended wooden block of mass M. If the block rises to height h, the initial velocity of the bullet will be

4. A bullet of mass m moving with a velocity u strikes a block of mass M at rest and gets embedded in the block. The loss of kinetic energy in the impact is

5. Select the false statement

6. A stationary particle explodes into two particles of masses x and y, which move in opposite directions with velocity v₁ and v₂. The ratio of their kinetic energies (E₁: E₂) is

7. A body of mass 10 kg moving with speed of 3 ms^-1 collides with another stationary body of mass 5 kg. As a result, the two bodies stick together. The KE of composite mass will be

8. A particle of mass m moving towards west with speed v collides with another particle of mass m moving towards south. If two particles stich to each other, the speed of the new particle of mass 2 m will be

9.

10. Particle A makes a perfectly elastic collision with another particle B at rest. They fly apart in opposite direction with equal speeds. If their masses are m_A & m_B respectively, then

11. A ball of mass m moving with velocity v collides head-on with the second ball of mass m at rest. If the coefficient of restitution is e and velocity of first ball after collision is v₁ and velocity of second ball after collision is v₂ then

12. An object of mass 80 kg moving with velocity 2 ms^-1 hit by collides with another object of mass 20 kg moving with velocity 4 ms^-1. Find the loss of energy assuming a perfectly inelastic collision

13. A stone of mass 1 kg is tied with a string and it is whirled in a vertical circle of radius 1 m. If tension at the highest point is 14 N, then velocity at lowest point will be

14. A particle of mass 200 g, is whirled into a vertical circle of radius 80 cm using a massless string. The speed of the particle when the string makes an angle of 60å¡ with the vertical line is 1.5 ms^-1. The tension in the string at this position is

15. A particle of mass 200 g is moving in a circle of radius 2 m. The particle is just ‰Û÷looping the loop‰Ûª. The speed of the particle and the tension in the string at highest point of the circular path are (g = 10 ms^-2)

16. The variation of potential energy U of a body moving along x-axis varies with its position (x) as shown in figure The body is in equilibrium state at

17. The variation of potential energy U of a system is shown in figure. The force acting on the system is best represented by

18. On a particle placed at origin a variable force F = -ax (where a is a positive constant) is applied. If U(0) = 0, the graph between potential energy of particle U(x) and x is best represented by

19. From a water fall, water is pouring down at the rate of 100 kg/s, on the blades of a turbine. If the height of the fall is 100 m, the power delivered to the turbine is approximately equal to

20. A car of mass m has an engine which can deliver power P. The minimum time in which car can be accelerated from rest to a speed v is