Atoms And Nuclei Question 11
Question: An electron has a mass of $ 9.1\times {{10}^{-31}}kg $ . It revolves round the nucleus in a circular orbit of radius $ 0.529\times {{10}^{-10}}metre $ at a speed of $ 2.2\times 10^{6}m/s $ . The magnitude of its linear momentum in this motion is [AFMC 1988]
Options:
A) $ 1.1\times {{10}^{-34}}kg-m/s $
B) $ 2.0\times {{10}^{-24}}kg-m/s $
C) $ 4.0\times {{10}^{-24}}kg-m/s $
D) $ 4.0\times {{10}^{-31}}kg-m/s $
Show Answer
Answer:
Correct Answer: B
Solution:
Linear momentum $ =mv=9.1\times {{10}^{-31}}\times 2.2\times 10^{6} $ $ =2.0\times {{10}^{-24}}kg-m/s $