(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A 92 kg fullback, running at 5.0 m/s, attempts to dive across the goal line for a touchdown. Just as he reaches the goal line, he is met head-on in midair by two 75 kg linebackers, one moving at 2.0 m/s and the other at 4.0 m/s. If they all become entangled as one mass, with what velocity do they travel? Does the fullback score?

2. Relevant equations

Momentum = Mass x velocity

P stands for Momentum

Pbefore = Pafter

3. The attempt at a solution

Here is what iv'e done so far. I want to make sure its right.

First I added both of the momentums of the linebackers and then I subtracted that momentum from the fullbacker's momentum to get a difference of 10 kg m/s and then divided that by the total mass of the 3 players combined.

P = M xv

P = Mv1 + Mv2

P = (75)(2) + (75)(4)

P = 150 + 300

P = 450 kg m/s

Pfullback = 92 x 5 = 460 kg m/s

Pchange = 460 kg m/s – 450 kg m/s

Pchange = 10 kg m/s

totalVelocity = totalMomentum/totalMass

Velocity = 10 kg m/s / 242kg

Velocity = 0.041 m/s

Yes the fullback scores.

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# Homework Help: Another momentum problem!

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