Question

which sentence describes newtons first law?
a. the action force applied by one object to another is opposite in direction to the reaction force.
b. unbalanced forces cause an object to move.
c. it takes a larger net force to accelerate an object at a greater rate.
d. forces always come in pairs that have the same magnitude.

Explanation:

Newton's first law states 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 means unbalanced forces cause a change in an object's state of motion (either from rest to moving or changing its velocity if already moving).

• Option A describes Newton's third law (action - reaction).
• Option C is related to Newton's second law (\(F = ma\), where \(F\) is force, \(m\) is mass, and \(a\) is acceleration).
• Option D is also part of the description of Newton's third law (equal magnitude of action - reaction pairs).

Answer:

B. Unbalanced forces cause an object to move.