Table of Contents
WORK POWER AND ENERGY JEE ADVANCED QUESTIONS
DOWNLOAD MOBILE APPLICATION TO LEARN MORE: WORK POWER AND ENERGY JEE ADVANCED QUESTIONS
32. The work done by all the forces (external and internal) on a system equals the change in
(a) Total energy
(b) Kinetic energy
(c) Potential energy
(d) None of these
Ans. (b)
33. Coefficient of friction between a tool and a grinding wheel is u as shown in Fig. 8-63. Power developed in water by the wheel of radius r running at n revolutions per second when tool is pressed to the wheel with F’ = kgf is
34. A spring of force constant k rests on a smooth floor, with one end fixed to a wall. A block of mass m hits the free end of the spring with velocity v. The maximum force exerted by the spring on the wall is
35. Consider two observers moving with respect to each other at a speed v along a straight line. They observe a block of mass m moving a distance / on a rough surface. The following quantities will be same as observed by the two observers
(a) Kinetic energy of the block at time /
(b) Work done by friction
(c) Total work done on the block
(d) Acceleration of the block
Ans. (d)
DOWNLOAD MOBILE APPLICATION TO LEARN MORE: WORK POWER AND ENERGY JEE ADVANCED QUESTIONS
36. A block m is kept stationary on the surface of an accelerating cage as shown in Fig. At the given instant, study following statements regarding the block.
(i) Normal reaction performs positive work on the block.
(ii) Frictional work done on the block is negative.
(iii) No net work is done by normal reaction and friction on the block.
Now mark the correct answer.
(a) Only statement (i) is correct
(b) Only statement (ii) is correct
(c) Only statement (iii) is correct
(d) All the statement correct
Ans. (a)
37. A small sphere is given vertical velocity of magnitude Vo = 5 m/s and it swings in a vertical plane about the end of a massless string shown in Fig. The angle with the vertical at which string will break, knowing that it can equal to twice the weight of the sphere, is
38. A block of mass M is hanging over a smooth and light pulley through a light string. The other end of the string is pulled by a constant force F. The kinetic energy of the block increases by 20 j in 1 s.
(a) The tension in the string is Mg
(b) The tension in the string is F
(c) The work done by the tension on the block in 20 j in the above 1’s
(d) The work done by the force of gravity in – 20 J in the above I s
Ans. (b)
More than one correct answer type
39. The potential energy U for a force field is such that U = – kxy, where k is a constant.
(a) The particle has a speed of 25 m/s at-4s
(b) The particle has an acceleration of 5 m/s2
(c) The acceleration of the particle is perpendicular to its initial velocity
(d) None of the above is correct
Ans. (a), (b), (c)
DOWNLOAD MOBILE APPLICATION TO LEARN MORE: WORK POWER AND ENERGY JEE ADVANCED QUESTIONS