NEET Solved Paper 2019 Question 4
Question: Ionized hydrogen atoms and $ \alpha $ -particles with same momenta enters perpendicular to a constant magnetic field, B. The ratio of their radii of their paths $ r _{H}:{r _{\alpha }} $ will be: [NEET 5-5-2019]
Options:
A) 4 : 1
B) 1 : 4
C) 2 : 1
D) 1 : 2
Show Answer
Answer:
Correct Answer: C
Solution:
$ r=\frac{mv}{qB}=\frac{p}{qB} $
$ r\propto \frac{1}{q} $
$ \frac{r _{H}}{{r _{\alpha }}}=\frac{{q _{\alpha }}}{q _{H}}=\frac{2e}{e} $
$ r _{H}:{r _{\alpha }}=2:1 $
