A bullet `(m_(1) = 25 g)` is fired with a velocity `400 ms^(-1)` get embedded into a bag of sand `(m_(2) = 4.9 kg)` suspended by a rope. The velocity of the bag is nearly :

Options

A. `0.2 ms^(-1)`
B. `8 ms^(-1)`
C. 4 `ms^(-1)`
D. `2 ms^(-1)`

Answer

d

Explanation

By conservation of momentum
`(25)/(100)xx400 = (4.9 +0.025) upsilon`
`upsilon=(10)/(4.925) = 2.030 ~~ 2 mg^(-1)`
(d) is the choice.