Question

5 which is the best inference about an object moving at a constant velocity? a no forces are acting on it b gravity is exerting the strongest force on it c the forces acting on it are in balance d it is stationary

Explanation:

To determine the best inference about an object moving at a constant velocity, we use Newton's first law of motion (the law of inertia). This law states that an object will remain at rest or in uniform motion (constant velocity) unless acted upon by a net external force. If the net force is zero, the forces are balanced.

• Option A: Incorrect. An object can have forces acting on it (e.g., gravity and normal force on a sliding block on a table) but still move at constant velocity if the forces are balanced. So, it's not necessary that no forces act on it.
• Option B: Incorrect. The concept of constant velocity is about the net force being zero, not about a specific force (like gravity) being the strongest. There's no requirement for gravity to be the strongest force.
• Option C: Correct. When an object moves at constant velocity, its acceleration is zero (since velocity is constant). From Newton's second law (\(F = ma\)), if \(a = 0\), the net force \(F = 0\). A net force of zero means the forces acting on the object are in balance (their vector sum is zero).
• Option D: Incorrect. An object moving at constant velocity is not stationary. Stationary means velocity is zero, while constant velocity means the object is moving with a non - zero, unchanging speed and direction.

Answer:

C. The forces acting on it are in balance