NEET UG 2008 — Chemistry Physical Chemistry

2008mcqeasy

If uncertainty in position and momentum are equal, then uncertainty in velocity is

Official previous-year question

Held on 30 Apr 2008 · Verified 9 Jul 2026.

Options

A
$\frac{1}{2 m} \sqrt{\frac{h}{\pi}}$
B
$\sqrt{\frac{h}{2 \pi}}$
C
$\frac{1}{m} \sqrt{\frac{h}{\pi}}$
D
$\sqrt{\frac{h}{\pi}}$

Did you get this right?

Solution

Key Idea: According to Heisenberg's uncertainty principle, it is impossible to determine simultaneously the position and momentum of a moving microscopic particle, ie, $\begin{aligned} & \Delta x \times \Delta p \geq \frac{h}{4 \pi} \\ & \because \Delta x \times \Delta p \geq \frac{h}{4 \pi} \end{aligned}$ Here $\Delta x=\Delta p$ and $\Delta p=m \cdot \Delta v$ $\begin{aligned} & \therefore \Delta v^2=\frac{h}{m^2 4 \pi} \\ & \text {or } \\ & \Delta v=\frac{1}{2 m} \sqrt{\frac{h}{\pi}} \end{aligned}$ Note: The uncertainty principle in terms of energy and time is given as $\Delta E \cdot \Delta t \geq \frac{h}{4 \pi}$

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NEET UG 2008 — Chemistry Physical Chemistry

2008mcqeasy

If uncertainty in position and momentum are equal, then uncertainty in velocity is

Official previous-year question

Held on 30 Apr 2008 · Verified 9 Jul 2026.

Options

A
$\frac{1}{2 m} \sqrt{\frac{h}{\pi}}$
B
$\sqrt{\frac{h}{2 \pi}}$
C
$\frac{1}{m} \sqrt{\frac{h}{\pi}}$
D
$\sqrt{\frac{h}{\pi}}$

Did you get this right?

Solution

Your note

NEET UG Physical Chemistry in other years

Keep practicing Physical Chemistry

Work through every NEET UG Physical Chemistry PYQ, year by year.

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NEET UG 2008 — Chemistry Physical Chemistry

Options

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Solution

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NEET UG Physical Chemistry in other years

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NEET UG 2008 — Chemistry Physical Chemistry

Options

Did you get this right?

Solution

Your note

NEET UG Physical Chemistry in other years

More NEET UG Physical Chemistry questions

Other Chemistry topics for NEET UG

Organic Chemistry

Inorganic Chemistry

Keep practicing Physical Chemistry