Block A ( ) slides on a horizontal table with a speed of toward Block B ( )
PHYSICS · Multi-part · CBSE · Physics · Work, Energy and Power · Work, Energy and Power
Problem
Block A (mA=2.0kg) slides on a horizontal table with a speed of 6.0ms−1 toward Block B (mB=3.0kg), which is initially at rest. The surface is rough with kinetic-friction coefficient μk=0.25. When the blocks collide, they stick together and continue sliding across the table until they come to rest.
(a) Determine the speed of the joined blocks immediately after impact.
(b) Calculate (i) the kinetic energy of Block A just before impact, (ii) the kinetic energy of the joined blocks just after impact, and (iii) the amount of mechanical energy transformed into other forms during the collision.
(c) Using the friction coefficient provided, compute the numerical value of the distance the stuck-together blocks travel before stopping.
(d) Show quantitatively that the work done by kinetic friction during the slide equals the loss of mechanical energy you found in part (c). Explain how this result is consistent with the law of conservation of energy.