Question

A 20 g bullet pierces through a plate of mass `M_(1)=1kg` and then comes to rest inside a second plate of mass `M_(2)=2.98` kg as shown in the figure. It is found that the two plates, initially at rest, now move with equal velocities, Find the percentage loss in the initial velocity of the bullet when it is between `M_(1)and M_(2)`. Neglect any loss of material of the plates due to the action of bullet

A. `50%`
B. `25%`
C. `100%`
D. `75%`

Answer 1

Correct Answer - B
`"mu"+M_(1)xx0=M_(1)V+"mu"_(1)("for"I^(st)"plate")`
`"mu"_(1)+M_(2)xx0=(m+M_(2))V("for"II^(nd)"plate")`
`"from "I^(st)&II^(nd)"equation"u_(1)/u=3/4`
`"so"%"loss"=(u_(1)-u)/uxx100%=25%`