Question

Which of the following is also known as the law of inertia?

(a) Newton’s second law of motion

(b) Newton’s third law of motion

(c) Aristotelian law of motion

(d) Newton’s first law of motion

I had been asked this question in homework.

This intriguing question comes from Forces in portion Laws of Motion of Engineering Physics I

Answer 1

The correct answer is (d) Newton’s first law of motion

To explain I would say: According to Newton’s first law of motion, every body continues in its state of rest or uniform motion unless an external force acts upon it. This inability of a body to change its state of rest or of uniform motion along a straight path is called inertia of a body. Hence the first law of motion is also called a law of inertia.