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4 years ago

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A 1400-kg car traveling east at 25m/s collides with a 1800-kg car traveling at a speed of 20m/s in a direction that makes angle

of 40degree south of west. the cars stick together after the collision. what is the magnitude and direction of the velocity of the cars after the collision?

1 answer:

julia-pushkina [17]4 years ago

7 0

M1*V1 + M2*V2 = M1*V + M2*V.
1400*25 + 1800*20[180+40]=1400*V+1800*V.
Divide both sides by 100:
14*25 + 18*20[220o] = 14V + 18V.
350 + 360[220o] = 32V.
350 - 276-231i = 32V.
74 - 231i = 32V.
242.6[-72.2o] = 32V.
V = 7.6m/s[-72.2o]=7.6m/s[72o] S. of E.

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<u>Change of Momentum</u>

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