Question

Which of the following statements is NOT one of Newton's Laws of Motion?

1) What goes up must come down.
2) In the absence of a net force acting upon it, an object moves with constant velocity.
3) The net force on an object equals the product of the object's mass and acceleration.
4) For any force, there always is an equal and opposite reaction force.

Answer 1

The statement 'What goes up must come down' is NOT one of Newton's Laws of Motion. Newton's actual laws involve the law of inertia, the relationship between force, mass, and acceleration, and the principle of action and reaction.

Step-by-step explanation:

The statement that is NOT one of Newton's Laws of Motion is: 'What goes up must come down.' This is often incorrectly attributed to Newton's laws but is not precisely stated in any of them. Here are Newton's actual laws of motion for clarification:

• • Newton's first law (also known as the law of inertia) states that an object at rest will stay at rest, and an object in motion will stay in motion with a constant velocity unless acted upon by a net external force.
  • Newton's second law asserts that the acceleration of an object is directly proportional to the net external force acting on it and is inversely proportional to its mass (net force equals mass times acceleration).
  • Newton's third law postulates that for every action, there is an equal and opposite reaction.