Assertion (A) : The position of electron can be determined with the help of an electronic microscope.
Reason (R) : The product of uncertainty in momentum and the uncertainty in the position of an electron cannot be less than a finite limit.

Options

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

Answer

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Analyze the Assertion
The assertion states: "The position of an electron can be determined with the help of an electronic microscope."

- In quantum mechanics, electrons do not have a definite position like macroscopic objects. Instead, they exist in a cloud of probabilities around the nucleus. While an electron microscope can be used to observe the effects of electrons, it cannot pinpoint the exact position of a single electron due to the principles of quantum mechanics.
- Therefore, the assertion is **false**.

### Step 2: Analyze the Reason
The reason states: "The product of uncertainty in momentum and the uncertainty in the position of an electron cannot be less than a finite limit."

- This statement refers to the Heisenberg Uncertainty Principle, which mathematically states that the product of the uncertainties in position (Δx) and momentum (Δp) is greater than or equal to a constant (h/4π), where h is Planck's constant.
- This means that if we try to measure the position of an electron very precisely (small Δx), the uncertainty in its momentum (Δp) must increase, and vice versa. Thus, the reason is **true**.

### Step 3: Conclusion
Based on the analysis:
- The assertion (A) is **false**.
- The reason (R) is **true**.

Thus, the correct answer is that the assertion is false, and the reason is true.

### Final Answer:
Assertion (A) is false, and Reason (R) is true.

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