JEE Main · 2025 · 29 Jan 2025 · Shift 2 · Atomic Structure

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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 :
  1. (A)Statement I is true but Statement II is false.
  2. (B)Both Statement I and Statement II are true.✓ Correct
  3. (C)Statement I is false but Statement II is true.
  4. (D)Both Statement I and Statement II are false.

Answer: (B)

Solution

The uncertainty principle, , forbids simultaneous exact knowledge of a particle's position and momentum — statement I is correct. Setting , the inequality becomes , so . Since , dividing through by mass gives
exactly the bound stated in statement II. Both statements are correct.

JEE Main · 2025 · 29 Jan 2025 · Shift 2 · Single correct option

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