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(A) : Contact forces like viscous force,...

(A) : Contact forces like viscous force, air resistance are electromagnetic in nature
(R) : At the microscopic level, all bodies are made of charged constituents

A

Both (A) and (R) are true and (R) is the correct explanation of (A)

B

Both (A) and (R) are true and (R) is not the

C

(A) is true but ( R) is false

D

Both (A) and (R ) are false

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze the assertion (A) and the reason (R) given in the problem. ### Step 1: Understand the Assertion (A) The assertion states that contact forces like viscous force and air resistance are electromagnetic in nature. - **Explanation**: Contact forces arise due to the interactions between the surfaces of objects. Viscous force occurs when a fluid flows over a surface, and air resistance acts on objects moving through the air. Both of these forces can be attributed to electromagnetic interactions at the microscopic level, where charged particles (like electrons and protons) in the atoms of the materials interact with each other. ### Step 2: Understand the Reason (R) The reason states that at the microscopic level, all bodies are made of charged constituents. - **Explanation**: This statement is true because all matter is composed of atoms, which contain charged particles (electrons and protons). The presence of these charged particles is fundamental to the nature of matter and explains why electromagnetic forces can arise between different bodies. ### Step 3: Analyze the Relationship Between A and R Now we need to determine if R correctly explains A. - **Explanation**: The reason (R) provides a valid explanation for the assertion (A). Since all bodies are made of charged constituents, the electromagnetic interactions between these charged particles lead to the contact forces like viscous force and air resistance. Therefore, R supports A by explaining the underlying principle of electromagnetic interactions that give rise to these forces. ### Conclusion Both the assertion (A) and the reason (R) are true, and R is the correct explanation of A. ### Final Answer Both A and R are true, and R is the correct explanation of A. ---
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