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

Car A has a greater mass than car B. Let:

- KA = the kinetic energy of car A

- KB = the kinetic energy of car B

- pA = the magnitude of the momentum of car A

- pB = the magnitude of the momentum of car B

- vA = the speed of car A

- vB = the speed of car B

a) If car A and car B have the same kinetic energy (KA = KB), then

2. Relevant equations

p=mv

Ke= .5(m)(v^2)

3. The attempt at a solution

I tried to set up a situation:

Car A- 10 kg Car B- 5kg Ke=20 J

.5(10)(v^2) = 20 .5(5)(v^2)=20

v= 2 m/s v= 2.828 THEREFORE Vb > Va

Pa=10(2) = 20 Pb=5(2.828) THEREFORE Pb < Pa

But the selection Pb<Pa and Vb>Va is wrong

Is there a flaw in my reasoning

thank you for your help

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# Homework Help: Energy:Momentum relationship

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