NEET Solved Paper 2018 Question 3
Question: At what temperature will the rms speed of oxygen molecules become just sufficient for escaping from the Earth’s atmosphere? (Given: Mass of oxygen molecule $ \text{(m)=2}\text{.76 }\times\text{ 1}{0^{\text{–26}}}kg $ Boltzmann’s constant $ {k_B}\text{=1}\text{.38 }\times\text{ 1}{0^{\text{–23}}}J{K^{\text{–1}}}\text{)} $ [NEET - 2018]
Options:
A) $ 5\text{.016 }\times\text{ 1}{0^{4}}\text{ K} $
B) $ 8\text{.360 }\times\text{ 1}{0^{4}}\text{ K} $
C) $ 2\text{.508 }\times\text{ 1}{0^{4}}\text{ K} $
D) $ 1\text{.254 }\times\text{ 1}{0^{4}}\text{ K} $
Show Answer
Answer:
Correct Answer: B
Solution:
- $ {V _{escape}}\text{=11200 m/s} $ Say at temperature T it attains $ {V _{escape}} $
So, $ \sqrt{\frac{3{k_B}T}{{m _{{O_2}}}}}=11200m/s $
On solving, $ \text{T=8}\text{.360 }\times\text{ 1}{0^{4}}\text{ K} $
