Q. A box contains $n$ molecules of a gas. How will the pressure of the gas be effected, if the number of molecules is made $2n$
A) Pressure will decrease
B) Pressure will remain unchanged
C) Pressure will be doubled
D) Pressure will become three times
Explanation
(c) If number of molecules in gas increases then number of collisions of molecules with walls of container would also increase and hence the pressure increses, $i.e.,\ P \propto N.$
$\Rightarrow \frac{P_{2}}{P_{1}} = \frac{N_{2}}{N_{1}} = \frac{2}{1} \Rightarrow P_{2} = 2P_{1}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.