A ball weighing 150g is moving with an initial velocity`overline(u)=(3overset(wedge)(i)+4overset(wedge)(j))ms^(-1)` After being hit by the player its final velocity is `overline(u)=(3overset(wedge)(i)+4overset(wedge)(j))ms^(-1)`What is the magnitude of change in momentam in kg `ms^(-1)`

Options

A. `1kg ms^(-1)`
B. `2kg ms^(-1)`
C. `1.5kg ms^(-1)`
D. `2.5kg ms^(-1)`

Answer

c

Explanation

Here change in momentum
`= -2 mu`
`-2xx(150)/(10000)[3hati+4hatj]`
`=(3000)/(1000)[-3hati-4hatj]`
`=-[(9)/(1)hati-(6)/(5)hatj]`
Magnitude `Ipl =sqrt((81)/(100)+(36)/(25))=(15)/(10)`
`1.5 kg m^(-1)S`Hence (C) is the right choice.