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Assertion: The familiar equation mg=R fo...

Assertion: The familiar equation `mg=R` for a body on a table is true only if the body is in equilibrium.
reason: The equality of mg and `R` has no connection with the third law.

A

If both assertion and reason are true and reason is the correct explanation of assertion.

B

If both assertion and reason are true and reason is the not correct explanation of assertion.

C

If assertion is true but reason is false

D

If both assertion and reason are false.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the given question, we need to analyze both the assertion and the reason provided. ### Step 1: Understand the Assertion The assertion states that the equation \( mg = R \) (where \( mg \) is the weight of the body and \( R \) is the normal reaction force from the table) is true only if the body is in equilibrium. - **Equilibrium Condition**: For an object to be in equilibrium, the net force acting on it must be zero. In this case, the forces acting on the body are: - Downward force due to gravity: \( mg \) - Upward force due to the normal reaction: \( R \) If the body is at rest on the table and not accelerating, these forces must balance each other, leading to the equation \( mg = R \). ### Step 2: Analyze the Reason The reason states that the equality of \( mg \) and \( R \) has no connection with Newton's third law of motion. - **Newton's Third Law**: This law states that for every action, there is an equal and opposite reaction. In this context, the action is the weight of the body acting downward, and the reaction is the normal force acting upward. However, the assertion \( mg = R \) is not a direct result of this law but rather a result of the equilibrium condition of the body. ### Step 3: Conclusion - **Assertion**: True (because \( mg = R \) holds true when the body is in equilibrium). - **Reason**: True (the equality of \( mg \) and \( R \) does not stem from the third law but from the equilibrium condition). ### Final Answer Both the assertion and reason are true, but the reason does not explain the assertion. Therefore, the correct option is: **Both assertion and reason are true, but the reason does not explain the assertion.**
To solve the given question, we need to analyze both the assertion and the reason provided. ### Step 1: Understand the Assertion The assertion states that the equation \( mg = R \) (where \( mg \) is the weight of the body and \( R \) is the normal reaction force from the table) is true only if the body is in equilibrium. - **Equilibrium Condition**: For an object to be in equilibrium, the net force acting on it must be zero. In this case, the forces acting on the body are: - Downward force due to gravity: \( mg \) - Upward force due to the normal reaction: \( R \) ...
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