Inertia and Newton's First Law

Steps:

• Identify the concept: Resistance to changes in motion or rest is inertia, from Newton's first law.
• Recall definition: Inertia depends on the object's mass, not other properties.
• Eliminate unrelated factors: Shape, area, and volume do not directly affect linear inertia.
• Confirm with physics: Mass measures inertia; heavier objects require more force to accelerate.

Why B is correct:

• Mass determines inertia, as per Newton's first law: An object's tendency to maintain its velocity is proportional to its mass.

Why the others are wrong:

• A: Shape affects rotational inertia but not linear resistance to motion changes.
• C: Surface area influences friction or drag, not inherent inertia.
• D: Volume relates to density but not directly to inertia without mass.

Final answer: B