Which of the following is an example of Newton's First Law?
a
A stationary book on the table must be picked up in order for it to move
b
Increasing the mass on an object experiencing the same force would decrease the acceleration
c
A baseball hits collides with a fence and they exchange forces
d
A rocket made with lighter composite materials will accelerate faster than a heavier one
Newton's First Law, often referred to as the law of inertia, states that an object at rest will stay at rest, and an object in motion will remain in motion with a constant velocity (speed and direction), unless acted upon by a net external force.
Based on this, the example that best demonstrates Newton's First Law is:
a. A stationary book on the table must be picked up in order for it to move.
This clearly illustrates the concept that an object at rest (the book on the table) will not move unless a force (picking it up) acts upon it.
The other options relate to different aspects of Newton's laws:
b. Talks about the concept of mass and acceleration, which is more related to Newton's Second Law (F = ma).
c. Discusses the interaction of forces which would relate to Newton's Third Law (for every action, there is an equal and opposite reaction).
d. Refers to the effect of mass on acceleration if the same force is applied, which is also related to Newton's Second Law.