Question

when an unbalanced force acts on an object, the change in the objects ____ or ____ depends on the size and direction of the force.

a. speed; direction
b. mass; speed
c. direction; mass
d. position; mass

Explanation:

Analyze the effect of an unbalanced force

Using the Balanced and Unbalanced Forces knowledge point

$$ \vec{F}_{\text{net}} = m\vec{a} eq 0 $$

An unbalanced net force causes acceleration, which is a change in velocity. Since velocity consists of both speed and direction, an unbalanced force can change an object's speed, its direction of motion, or both. Mass is an intrinsic property of the object and does not change when a force is applied.

Evaluate the given options

Using the Balanced and Unbalanced Forces knowledge point

• Option A: speed; direction (Both can change due to an unbalanced force)
• Option B: mass; speed (Mass does not change due to an applied force)
• Option C: direction; mass (Mass does not change due to an applied force)
• Option D: position; mass (Mass does not change due to an applied force)

Therefore, Option A is the correct choice.

Answer:

• A. speed; direction (Correct answer)
• B. mass; speed
• C. direction; mass
• D. position; mass