Question

When a car is stationary, there is no net force acting on it. During pick-up, it accelerates. This happens due to
(a) net external force
(b) net internal force
(c) may be external or internal force
(d) None of the above

Answer 1

Net external force.(newton's first law said that a body on motion remains on motion and a body at rest remaines at rest unless any EXTERNAL force is applied)

Answer 2

Answer:

If a car is stationary, there is no net force acting on it. During pick-up, it accelerates. This occurs due to (a) net external force.

Explanation:

• The vector sum of all the forces exerted on a system is known as the net external force.
• A body may be subjected to an endless number of forces. However, there will always be only one net external force acting on that body, which is the consequence of all those forces operating on it.
• There is no net force applied to the car when it is motionless. It accelerates during pick-up. This can only happen as a result of a net external force. It has to be a force from the outside. There is no internal force that can explain the car's acceleration.

• The only external force that could be present on the road is friction. The car accelerates as a whole due to the frictional force. There is no net external force when the car moves at a constant speed.