A sample of an ideal gas is slowly compressed to one-half its original volume with no change in temperature. What happens to the average speed of the molecules in the sample?

Question

A sample of an ideal gas is slowly compressed to one-half its original volume with no change in temperature.  What happens to the average speed of the molecules in the sample?

anonymous · Answer

$$Vavg =  \sqrt{8RT/\pi M}$$So I thing that there should be no change in the Vavg.
But we are decreasing volume, this will affect the collision frequency..... So i'm little confused.

anonymous · Answer

oh nvm i found the formula 
$$v=\sqrt{\frac{ 3kT }{ m }}$$ and since Volume isn't related there wouldn't be any change

anonymous · Answer

That's the formula for Vrms not Vavg.

anonymous · Answer

Oh yeah you're right. But I'm not seeing that other formula in my book

anonymous · Answer

Don't worry thee formula which I wrote is correct. Just learn it along with Vrms.