A car of mass m starts from rest and acquires a velocity along east $\mathbf{v}=v\hat{\mathbf{i}}(v>0)$ in two seconds.
Assuming the car moves with uniform acceleration, the force exerted on the car is

Given, mass of the car = m
As car starts from rest, u = 0
Velocity acquired along east, $\mathbf{v}=v\hat{\mathbf{i}}$
Duration, t = 2 s
From first equation of motion,

$v=u+at\Rightarrow v\hat{\mathrm{i}}=0+\mathbf{a}\times 2\Rightarrow \mathbf{a}=\frac{v}{2}\hat{\mathbf{i}}$

Force, $\mathbf{F}=m\mathbf{a}=\frac{mv}{2}\hat{\mathbf{i}}$

Hence, force acting on the car is  $\frac{mv}{2}$ towards east due to friction on the tires exerted by the road.