physics help 2?

Question

Two cars A and B, are travelling with the same speed of 40.0m/s, each having started from rest. Car A has a mass of 1.20x10^3kg and car B has a mass of 2.0x10^3 kg . compared to the work required to bring car A up to speed, how much aditional work is required to bring car B upto speed?

Answer 1

ignoring friction, the work is equal to the KE
.5*m*v^2
sine the v is equal for both the ratio is equal to the ratio of the masses

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