In a football game, a tackle running at a constant speed of 5 m/s tackles a stationary receiver. The two fly off horizontally at 4 m/s, before they hit the ground and begin to slow down. If the mass of the tackle is 105 kg,

Question

a.) What is the mass of the receiver?
1Your answer is incorrect.

b.) Calculate the kinetic energy of the tackle-receiver system before and after the collision.

I tried the formula for question a.) to set the initial and final momentum to be equal, but I keep getting the mass wrong...help?

Answer 1

Mt*5 m/s = (Mt + Mr)*4
(Mt+Mr)/Mt = 1 + Mr/Mt = 5/4

The receiver has only 1/4 the mass of the tackle, 26.3 kg. He should not be playing football. Are you sure you did not make a typing error?