Question

FALSE statement about third law of motion is

• A. Forces in nature always occur between pairs of bodies
• B. If \(\vec{F}\) is a force on body A by body B then -\(\vec{F}\) is the force on B by body A
• C. Action and reaction forces are simultaneous forces
• D. Any of the two mutual forces can be called action and the other reaction
• E. There is cause-effect relation between action and reaction

Hint:

Always remember: Action and reaction never act on the same body. That's why they don't cancel each other out to zero net force on a single object.

Answer 1

Answer: (E)

Step 1: Understanding the Concept:
Newton's Third Law of Motion states that for every action, there is an equal and opposite reaction. These forces act on different bodies.

Step 3: Detailed Explanation:
- Option A: True. Forces always exist in pairs (interaction).
- Option B: True. \(\vec{F}_{AB} = -\vec{F}_{BA}\).
- Option C: True. Action and reaction forces occur at the same instant. There is no time lag between them.
- Option D: True. Which force is called "action" and which is "reaction" is arbitrary.
- Option E: False. A "cause-effect" relationship implies that the action happens first and then the reaction follows after a small interval. In reality, they are simultaneous. There is no such thing as an action "causing" a reaction; they are just two parts of a single interaction.

Step 4: Final Answer:
Statement E is false.