Question

1. describe how do balanced forces affect an objects motion?
2. explain why does the couch move in the bottom picture, but not in the top?
3. infer an object moves at a constant speed along a circular path. is the object experiencing balanced or unbalanced forces? explain your answer.

Explanation:

• Question 5: Balanced forces mean the net force is zero. According to Newton's first law, if the net force on an object is zero, the object's velocity (which includes both speed and direction) does not change. So, if an object is at rest, it stays at rest. If it is moving, it continues to move at a constant speed in a straight - line (constant velocity).
• Question 6: In the top picture, the forces acting on the couch are balanced (e.g., equal and opposite pushing forces from two sides, or pushing force and frictional force are equal). In the bottom picture, the forces are unbalanced. For example, if one person pushes harder (or there is a net force in one direction), the net force is not zero. According to Newton's second law ($F = ma$, where $F$ is the net force, $m$ is the mass, and $a$ is the acceleration), when $F

eq0$, $a
eq0$, so the couch accelerates (moves).

• Question 7: An object moving at a constant speed along a circular path has a changing velocity (because velocity is a vector, and the direction of motion is constantly changing). According to Newton's second law ($F = ma$), if the velocity is changing ($a

eq0$), then the net force ($F$) is not zero. Unbalanced forces are forces where the net force is not zero. So, the object is experiencing unbalanced forces.

Answer:

• Question 5: Balanced forces result in no change in an object's motion. If the object is at rest, it remains at rest. If it is moving, it continues to move at a constant velocity (constant speed in a straight - line).
• Question 6: In the top picture, forces on the couch are balanced (net force \(F_{net}=0\)). In the bottom picture, forces are unbalanced (\(F_{net}

eq0\)). By Newton's second law (\(F = ma\)), when \(F_{net}
eq0\), the couch accelerates (moves).

• Question 7: The object is experiencing unbalanced forces. Although the speed is constant, the direction of motion (velocity) is changing. A change in velocity implies an acceleration (\(a

eq0\)). By Newton's second law (\(F = ma\)), if \(a
eq0\), then \(F_{net}
eq0\) (unbalanced forces).