Assertion: The minimum number of vectors of unequal magnitude required to produce zero resultant is three.
Reason: Three vectors of unequal magnitude which can be represented by the three sides of a triangle taken in order, produce zero resultant.

Options

A. Reynolds number and coefficient of friction
B. Curie and frequency of a light wave
C. Latent heat and gravitational potential
D. Planck's constant and torque

Answer

To solve the question regarding the assertion and reason about vectors, let's break it down step by step:

### Step 1: Understand the Assertion
The assertion states that the minimum number of vectors of unequal magnitude required to produce a zero resultant is three.

### Step 2: Analyze the Reason
The reason provided states that three vectors of unequal magnitude can be represented by the three sides of a triangle taken in order, which can produce a zero resultant.

### Step 3: Explore the Concept of Resultant Vectors
To understand why three vectors are needed, we should recall that:
- Two vectors can produce a zero resultant if they are equal in magnitude and act in opposite directions (180 degrees apart).
- However, if the vectors are of unequal magnitudes, they cannot cancel each other out with just two vectors.

### Step 4: Triangle Law of Vectors
According to the triangle law of vectors:
- If three vectors can be arranged in such a way that they form a triangle when placed head to tail, then their resultant is zero.
- This means that if we have three vectors \( \vec{A}, \vec{B}, \vec{C} \) such that \( \vec{A} + \vec{B} + \vec{C} = 0 \), they can be represented as the sides of a triangle.

### Step 5: Conclusion
Thus, the assertion is true because at least three vectors of unequal magnitudes are required to achieve a zero resultant. The reason is also true as it correctly explains why three vectors can produce a zero resultant by forming a triangle.

### Final Answer
Both the assertion and the reason are true, and the reason is a correct explanation of the assertion.

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