Given below are two statements: Statement (I): It is impossible to specify simultaneously, with arbitrary precision,…
Structure of Atom · Class 11 · JEE Main Previous Year Question
Given below are two statements:
Statement (I): It is impossible to specify simultaneously, with arbitrary precision, both the linear momentum and the position of a particle.
Statement (II): If the uncertainty in the measurement of position and uncertainty in measurement of momentum are equal for an electron, then the uncertainty in the measurement of velocity is .
In the light of the above statements, choose the correct answer from the options given below:
- a
Statement I is true but Statement II is false.
- b✓
Both Statement I and Statement II are true.
- c
Statement I is false but Statement II is true.
- d
Both Statement I and Statement II are false.
Both Statement I and Statement II are true.
🧠 The "Aha!" Moment Heisenberg's Uncertainty Principle is the "speed limit" of information in the universe. It isn't a failure of our tools, but a fundamental property of nature. Statement I is the direct law. Statement II is a specific mathematical case where we try to balance the scales perfectly between position and momentum.
🗺️ The Proof for Statement II
- The Principle:
- The Condition: If uncertainties in position and momentum are equal ():
- Link to Velocity: Since momentum uncertainty is : Both statements are mathematically and conceptually flawless.
⚡ The Equal Uncertainty Trap If you ever see a problem where , remember that the uncertainty in velocity will always involve a square root of Planck's constant (). It’s a common "numerical shortcut" in competitive physics.
⚠️ Watch the Pi! simplifies to . Don't let the placement of the throw you off; it's simply the square root of the that sits inside the original principle.
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