Question

An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force. This statement is known as:
A) Newton’s first law of motion
B) Newton’s second law of motion
C) Newton’s third law of motion
D) Newton’s law of gravitation

Answer 1

Hint: The property of the body to remain in its state of rest or uniform speed is termed as Inertia of the body. Newton defined this property in one of the laws of motion. We have to find in which law the inertia is described.

Complete step by step answer:
We have given that an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force. This statement relates to the inertia of the body. Thus it will be related to the law of inertia or Newton’s first law of motion.
It is described that if there is no external unbalanced force acting on the object it will not have a change in velocity or it maintains constant velocity. If the object has no velocity that is at rest, then it will remain at rest. The tendency of the body is called inertia.
Newton’s second law of motion describes the rate of change of velocity. And Newton’s third law of motion describes the equal and opposite forces. And the Law of gravitation is all about the force of attraction or repulsion.

Thus, the answer is option A.

Note:
If the external forces are balanced only the body will remain in its state. This is because the external forces will cancel each other to balance. If the external forces are not balanced it will change the state of rest or uniform motion.