A 140g ball, in horizontal flight with a speed `v_(1)` of 39.0 m/s. is sturck by a bat. After leaving the bat, the ball travel in the opposite direction with speed `v_(2)=39.0 m//s`. If the impact time `Deltat` for the ball-bat collision is 1.20ms, what average net force acts on the ball

Options

A. 1308N
B. 1090N
C. 9100N
D. 980N

Answer

C

Explanation

Here mass of ball, m=140g=0.14kg
initial velocity `v_(1)=39m//s`,
final velocity `v_(2)=-39m//s`,
impact time `Deltat=1.20ms`
impulse, I=change in momentum.
`Deltap=mv_(2)-mv_(1)=m(v_(2)-v_(1))`
`=0.14(-39-39)`
`=-10.92 kg m//s`
`therefore F_("mv")=(I)/(Deltat)=(10.92kg m//s)/(1.20xx10^(-3)s)=91xx10^(2)N`