Answer:
Given:
Mass of elephant = 5240 kg
The initial speed of the elephant = 4.55 m/s
Mass of the rubber ball, m, = 0.15 kg
Inital speed of the rubber ball, v = 7.81 m/s
On substitution in [tex]V_{2f}[/tex] = [tex][\frac{2m_{1} }{m_{1} +m_{2} } ]V_{1f}[/tex] + [tex][\frac{m_{2}-m_{1}}{m_{1}+m_{2} } ] v_{2f}[/tex]
[tex]V_{2f}[/tex] = [tex][\frac{2*5240_{} }{5240_{} +0.15_{} } ](-4.55_{})[/tex] + [tex][\frac{0.15_{}-5240_{}}{5240_{}+0.15_{} } ] (7.81_{})[/tex]
a) The negatıve sign shows that the ball bounces back in the direction opposite to the incident
b) it is clear that the velocity of the ball increases and therefore it is kinetic energy
. The ball gains kinetic energy from the elephant.
