Car a hits car b (initially at rest and of equal mass) frombehind while going 35 m/s. immediately after the collision, car bmoves forward at 25 m/s and car a is at rest. what fraction of theinitial kinetic energy is lost in the collision?
my approach:
how exactly do you approach this question? at first, i thoughtusing the the formula σkei = σkef. then, to find the fraction just divide the former from the latter. but is it that cut and dry?
before collision:
via= 35 m/s
vib = 0 m/s
vfa = 0 m/s
vfb =25 m/s
m1 = m2

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