Assertion (A): In Fleming's Left Hand Rule, the direction of magnetic field, force and current are mutually perpendicular.
Reason (R): Fleming's Left hand Rule is applied to measure the induced current.

Options

A. Both A and R are true and R is the correct explanation of A.
B. Both A and R are true but R is NOT the correct explanation of A
C. A is true but R is false.
D. A is false and R is true

Explanation

To solve the question regarding the assertion and reason related to Fleming's Left Hand Rule, we will analyze both statements step by step.

### Step 1: Understand the Assertion (A)
The assertion states that in Fleming's Left Hand Rule, the direction of the magnetic field, force, and current are mutually perpendicular.

- **Explanation**: Fleming's Left Hand Rule is a mnemonic used to determine the direction of force experienced by a current-carrying conductor in a magnetic field. According to this rule:
- The **thumb** represents the direction of the **force** (motion).
- The **index finger** represents the direction of the **magnetic field**.
- The **middle finger** represents the direction of the **current**.

When the fingers are arranged in this manner, they are indeed mutually perpendicular to each other. Thus, the assertion is **correct**.

### Step 2: Understand the Reason (R)
The reason states that Fleming's Left Hand Rule is applied to measure the induced current.

- **Explanation**: This statement is incorrect. Fleming's Left Hand Rule is primarily used to determine the direction of the force acting on a conductor in a magnetic field when current flows through it. It does not measure induced current; that is typically associated with Fleming's Right Hand Rule, which is used in the context of electromagnetic induction (where a changing magnetic field induces a current).

### Step 3: Conclusion
Based on the analysis:
- Assertion (A) is **true**.
- Reason (R) is **false**.

Thus, the correct answer to the question is that the assertion is true, but the reason is false.

### Final Answer
- Assertion (A) is true.
- Reason (R) is false.
- The correct option is: Assertion is true, Reason is false.

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