Question

The uncertainity in position of an electron and helium atom are same. If the uncertainity in momentum for the electron is $32\times {10}^5$, then the uncertainity in momentum of helium atom will be__________.

• A. $32\times {10}^5$
• B. $16\times {10}^5$
• C. $8\times {10}^5$
• D. None

Answer 1

The correct option is A $32\times {10}^5$

According to Heisenberg's Uncertainity principle:

$\Delta x.\Delta p\ge h/4\pi$

therefore for a known amount of uncertainty in position, all particles will have same uncertainty in momentum.

given $\Delta p_e=32\times {10}^5$

thus, $\Delta p_{He}=32\times {10}^5$

option A is correct