Car A runs a red light and broadsides Car B, which is waiting to turn left. Car A has a mass of 2000 KG. Car B has a mass of 1500 KG. After the impact, the cars stick together and slide away at a speed of 9.1 m/s. How fast was Car A going when it hit Car B?
2007-01-20 07:51:31 · 2 answers · asked by BadRomance 2 in Science & Mathematics ➔ Physics
I checked the book before posting this question here, like I always do, but I couldn't find anything...
2007-01-20 08:03:50 · update #1
Basically, Momentum before must equal momentum after. Momentum = mass x velocity.
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Momemtum after collision was:
3500kg x 9.1m/s = 31850kgm/s
(3500kg is the total mass of both cars sinc they stuck together after the collision as one body)
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Original momentum must equal 31850kgm/s:
Car B had 0kgm/s momentum because its velocity was 0m/s.
Car A had all the momentum therefore:
2000kg x ?m/s = 31850kgm/s
Hence ?m/s = 31850kgm/s / 2000kg
?= 15.925m/s
Car A was travelling at 15.925m/s
2007-01-20 08:15:49 · answer #1 · answered by Mubz 4 · 1⤊ 0⤋
oh my god im takin pyhisics right now and ummm yea...sorry isnt there an equation in ur books its like m1*m2 / speed should equally initial speed
2007-01-20 15:58:36 · answer #2 · answered by Ambelry A 1 · 0⤊ 0⤋