Question

question 1.
which of the following statements is the main difference between balanced and unbalanced forces?
a. unbalanced forces are only present in moving objects, while balanced forces are always present in stationary objects.
b. balanced forces lead to no change in motion, whereas unbalanced forces lead to motion.
c. balanced forces are larger than unbalanced forces.
d. unbalanced forces occur only when objects collide.

Explanation:

• Option A: Unbalanced forces can also act on stationary objects (e.g., a stationary object starting to move due to unbalanced forces). Balanced forces can act on moving objects (e.g., an object moving at a constant velocity has balanced forces). So this option is wrong.
• Option B: According to Newton's first law, when forces are balanced (\(F_{net}=0\)), there is no acceleration (\(a = 0\)), so no change in motion (either at rest or moving at a constant velocity). When forces are unbalanced (\(F_{net}

eq0\)), there is an acceleration (\(F_{net}=ma\), \(m
eq0\)), which leads to a change in motion (can be starting from rest, stopping, or changing velocity). This option is correct.

• Option C: The magnitude comparison between balanced and unbalanced forces is not the defining characteristic. Balanced forces have \(F_{net}=0\) (sum of forces is zero), unbalanced forces have \(F_{net}

eq0\). It's about the net force, not individual force magnitudes. So this option is wrong.

• Option D: Unbalanced forces can occur in many situations, not just when objects collide (e.g., a force applied to a single object to make it move). So this option is wrong.

Answer:

B. Balanced forces lead to no change in motion, whereas unbalanced forces lead to motion.