A bullet of mass 10g strikes a fixed target and penetrates 8 cm into it before coming to rest. If the average force of resistance offered by the target is 100 N with what velocity does it strike ? :

Options

A. `10 ms^(-1)`
B. `20 ms^(-1)`
C. `30 ms^(-1)`
D. `40 ms^(-1)`

Answer

d

Explanation

Work done = change in K.E.
`Fxxx=1/2mv^(2)`
`:. v=sqrt((2Fx)/(m))=sqrt((2xx100xx(8)/(100))/((10)/(100)))=40 ms^(-1)`