Answer:
[tex]m_{receiver}=115Kg*3.1/(1.6)-115Kg=107.8Kg[/tex]
Explanation:
The football players collide in a completely inelastic collision, in other words they have the same velocity after the collision, this velocity has a magnitude V=1.6m/s.
We need to use the conservation of momentum Law, the total momentum is the same before and after the collision, at the initial point the receiver does not have any speed
[tex]m_{tackler}*v_{tackler}=(m_{tackler}+m_{receiver})V[/tex] (1)
We solve in order to find the receiver mass:
[tex]m_{receiver}={m_{tackler}*v_{tackler}/V}-m_{tackler}[/tex]
[tex]m_{receiver}=115Kg*3.1/(1.6)-115Kg=107.8Kg[/tex]