Question 14

A body in motion tends to remain in motion, a force will change an object's speed or direction, and for every action, there is an equal and opposite reaction.

These statements accurately reflect principles derived from Newton's laws of motion, specifically relating to inertia, the effect of force, and the action-reaction principle.

A) A body in motion tends to remain in motion.

This statement is a clear representation of Newton's First Law of Motion, which defines inertia. It asserts that an object in motion will continue in that state unless acted upon by an external force, demonstrating the concept of motion persistence.

B) Resisting forces always cause friction.

This statement is incorrect in the context of Newton's laws. While friction is a type of resisting force, not all resisting forces are frictional. For example, air resistance is a resisting force that does not imply a frictional interaction on surfaces. Thus, this statement does not accurately reflect Newtonian mechanics.

C) A force will change an object's speed or direction.

This statement accurately reflects Newton's Second Law of Motion, which states that an unbalanced force acting on an object will cause it to accelerate, thereby changing its speed or direction. This principle is foundational in understanding how forces affect motion.

D) Inertia is a force based on the mass of an object.

This statement is incorrect as it confuses the concept of inertia with force. Inertia is not a force; rather, it is the property of an object that resists changes in its state of motion, directly related to its mass. Therefore, it does not align with Newton’s laws.

E) For every action, there is an equal and opposite reaction.

This statement encapsulates Newton's Third Law of Motion, which indicates that forces always occur in pairs. When one object exerts a force on another, the second object exerts a force of equal magnitude and opposite direction back on the first object, demonstrating the interrelation of forces.

Conclusion

Statements A, C, and E accurately reflect the core principles of Newton's laws of motion, illustrating the concepts of inertia, force's impact on motion, and action-reaction pairs. In contrast, options B and D fail to correctly represent these laws, either by mischaracterizing forces or misunderstanding inertia, thereby confirming that A, C, and E are the correct choices.