Atomic Structure Question 420
Question: The uncertainty in the position of an electron $ (mass=9.1\times 10^{28}g) $ moving with a velocity of $ 3.0\times 10^{4}cm{s^{-1}} $ accurate up to 0.011 % will be
Options:
A) 1.92 cm
B) 7.68 cm
C) 0.175 cm
D) 3.84 cm
Show Answer
Answer:
Correct Answer: C
Solution:
- $ \Delta x.\Delta p=\frac{h}{4\pi } $ or $ \Delta x.m\Delta v=\frac{h}{4\pi }; $
$ \Delta v=\frac{0.011}{100}\times 3\times 10^{4}=3.3cm{s^{-1}} $
$ \Delta x=\frac{6.6\times {10^{-27}}}{4\times 3.14\times 9.1\times {10^{-28}}\times 3.3}=0.175cm $