(A) : A tangent galvanometer is used for measuring current.
(R) : Tangent galvanometer reads current directly.

Options

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 correct explanation of 'A'
C. 'A' is true and 'R' is false
D. 'A' is false and 'R' is false

Answer

To solve the question regarding the assertion (A) and reason (R) about the tangent galvanometer, we will analyze both statements step by step.

### Step 1: Analyze the Assertion (A)
The assertion states: "A tangent galvanometer is used for measuring current."

- **Explanation**: A tangent galvanometer is indeed used to measure the electric current. It operates based on the principle that a current-carrying conductor produces a magnetic field. The tangent galvanometer measures the angle of deflection of a magnetic needle placed in the magnetic field created by the current. This deflection is proportional to the current flowing through the conductor.

- **Conclusion**: The assertion is **True**.

### Step 2: Analyze the Reason (R)
The reason states: "Tangent galvanometer reads current directly."

- **Explanation**: While the tangent galvanometer is used to measure current, it does not read the current directly. Instead, it measures the deflection of a magnetic needle and requires calculations to relate this deflection to the current flowing through the conductor. The current is determined indirectly by comparing the magnetic field produced by the current with the Earth's magnetic field.

- **Conclusion**: The reason is **False**.

### Final Conclusion
- Assertion (A) is **True**.
- Reason (R) is **False**.

Thus, the correct option is that the assertion is true, but the reason is false.

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