Q. 175.0( 2 Votes )

# Consider the situation of the previous question from a frame moving with a speed v parallel to the initial velocity of the block. (a) What are the initial and final kinetic energies? (b) What is the work done by the kinetic friction?

Answer :

(i) In this condition, the let’s consider the velocity of the ball to be and the velocity of the frame to be.

Relative velocity of the object w.r.t to the frame

Initial kinetic energy of the object

final kinetic energy of the object

(ii) Work done by the kinetic friction= final kinetic energy – Initial kinetic energy

Rate this question :

The kinetic energy of a particle continuously increases with time.

HC Verma - Concepts of Physics Part 1Which of the diagrams shown in Fig. 6.7 represents variation of total mechanical energy of a pendulum oscillating in air as function of time?

Physics - ExemplarA smooth sphere of radius R is made to translate in a straight line with a constant acceleration α. A particle kept on the top of the sphere is released from there at zero velocity with respect to the sphere. Find the speed of the particle with respect to the sphere as a function of the angle θ it slides.

HC Verma - Concepts of Physics Part 1The bob of a pendulum at rest is given a sharp hit to impart a horizontal velocity where l is the length of the pendulum. Find the tension in the string when (a) the string is horizontal, (b) the bob is at its highest point and (c) the string makes an angle of 60^{o} with the upward vertical.