Simultaneous determination of exact position and momentum of an electron is.

Options

A. Possible
B. Impossible
C. Sometimes possible sometimes impossible
D. None of the above

Explanation

To solve the question regarding the simultaneous determination of the exact position and momentum of an electron, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Concept**: The question revolves around the Heisenberg Uncertainty Principle, which states that it is impossible to simultaneously know both the exact position (Δx) and exact momentum (Δp) of a particle, such as an electron.

2. **Heisenberg Uncertainty Principle**: The principle can be mathematically expressed as:
\[ \Delta x \cdot \Delta p \geq \frac{h}{4\pi} \]
where \( \Delta x \) is the uncertainty in position, \( \Delta p \) is the uncertainty in momentum, and \( h \) is Planck's constant.

3. **Implications of Measurement**: When we attempt to measure the position of an electron, we typically use a photon (light). The interaction of the photon with the electron changes its momentum. Thus, measuring the position affects the momentum, leading to uncertainty.

4. **Conclusion**: Due to the nature of quantum mechanics, it is fundamentally impossible to determine both the exact position and momentum of an electron simultaneously. Therefore, the answer to the question is that simultaneous determination of exact position and momentum of an electron is not possible.

### Final Answer:
The simultaneous determination of the exact position and momentum of an electron is impossible.

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