A 140 kg lineman moving west tackles a 90.0 kg fullback moving east at 7.60 m/s. After the collision, both players move together east at 1.0 m/s. What was the fullbacks speed before the collision

The answer is 4f======since electrostatic force is given by    we let f be the electrostatic force when  r = 1 m    if we let  denote the electrostatic force when the distance is decreased so that r = 0.5m, then    we established earlier that f = kq₁q₂. therefore    the force will now be 4f.

What are you asking

Well i am not very good at this but  i would be guessing 1hope i