JEE Main20204 Sep 2020Morning ShiftPhysicsCenter of Mass, Momentum and CollisionActual
Blocks of masses m , 2 m , 4 m and 8 m are arranged in a line of a frictionless floor. Another block of mass m , moving with speed υ along the same line (see figure) collides with mass m in perfectly inelastic manner. All the subsequent collisions are also perfectly inelastic. By the time the last block of mass 8 m starts moving the total energy loss is p% of the original energy. Value of ‘ p ’ is cl
Options
- A77
- B94
- C37
- D87
Correct answer
B. 94
Step-by-step solution
Inelastic collision mv = 16   mv 1 ΔK   loss = 1 2 mv 2 − 1 2 16 M v 16 2 = 1 2 mv 2 − 1 2 M v 2 16 = 1 2 mv 2 15 16 %   ΔK   loss = 1 2 mv 2 15 16 1 2 MV 2 × 100 = 15 16 × 100 = 93 .75 %