Question

a toy cars engine pushes it forward at a constant speed. what happens if the force provided by the engine decreases?
a. the toy cars mass increases.
b. the toy cars speed remains constant.
c. the toy cars state of motion changes.
d. the toy car gains inertia.

Explanation:

When the toy car is moving at a constant speed, the force provided by the engine is equal to the resistive forces (like friction). If the engine - provided force decreases, the net force on the car is no longer zero. According to Newton's second law \(F = ma\) (where \(F\) is the net force, \(m\) is the mass, and \(a\) is the acceleration), a non - zero net force will cause a change in the car's velocity (its state of motion).
The mass of the toy car is an inherent property and does not change due to a change in the engine force. Inertia is related to mass (\(I = m\)), so it also does not change. And if the force balance is disrupted (engine force < resistive forces), the speed will not remain constant.

Answer:

C. The toy car's state of motion changes