Question:
A car of mass m starts from rest and acquires a velocity along the east
$v=v \hat{i}$ in two seconds. Assuming the car moves with uniform acceleration, the force exerted on the car is
(a) mv/2 eastward and is exerted by the car engine
(b) mv/2 eastward and is due to the friction on the tyres exerted by the road
(c) more than mv/2 eastward exerted due to the engine and overcomes the friction of the road
(d) mv/2 exerted by the engine
Solution:
The correct answer is (b) mv/2 eastward and is due to the friction on the tyres exerted by the road