Most Important Selected Qs for JEE AdvancedPhysicsCenter of Mass, Momentum and Collision
A penguin of mass m stands at the right edge of a sled of mass 3 m and legnth . The sled lies on frictionless ice. The penguin starts moving towards left, reaches the left end and jumps with a velocity u at an angle with horizontal relative to ground. (Neglect the height of the sled)
Options
- ATill the penguin reaches the left end, the sled is displaced by l 4 .
- BTill the penguin reaches the left end, the sled is displaced by l 3 .
- CAfter jumping, it will fall on the ground at a distance 4 3 u^2 2 g from the left end of the sled.
- DAfter jumping, it will fall on the ground at a distance 3 4 u^2 2 g from the left end of the sled.
Correct answer
C. After jumping, it will fall on the ground at a distance 4 3 u^2 2 g from the left end of the sled.
Step-by-step solution
gathered (A) S _ CM = m ₁ ~S ₁+ m ₂ ~S ₂ ~m ₁+ m ₂ 0= (3 ~m )(- x )+( m )( - x ) 3 ~m + m x = l 4 gathered (C) aligned & T = 2 u g & Displacement of sled in this time = ( u 3 ) ( 2 u g )= 1 3 ( u^2 2 g ) aligned Total distance between penguin and left end of sled = 4 3 ( u^2 2 g )