Physics

Problem

For a car of mass

m

that starts from rest on a horizontal road, its engine supplies a constant power

P

. Neglect all resistive forces. The instantaneous acceleration

a

of the car varies with time

t

as a)

a\propto t^{1/2}

a\propto t^{-1}

a\propto t^{-1/2}

a

is constant