A car of mass m starts from rest on a horizontal road. Its engine supplies constant power P and resistive forces are negligible. Its speed after time t is:
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A car of mass m starts from rest on a horizontal road. Its engine supplies constant power P and resistive forces are negligible. Its speed after time t is:

G1 Physics · Accepted Answer

Constant power gives dK/dt=P. Starting from rest, ½mv²=Pt. Therefore v=√(2Pt/m).