00:01
Hi.
00:02
So we are to determine the temperature in terms of kelvin of a sample of helium with a root mean square speed of 450 meters per second.
00:10
So this is the formula that we will use, brms, the root mean square speed, is equivalent to the square it of 3 multiplied by r, the gas constant, to the temperature over the molar mass of the gas.
00:23
So let's rearrange this so we could solve for the temperature.
00:29
We'll just raise both sides to the part of two, so we could remove the square.
00:33
Symbol so we'll have v rm s squared is equivalent to 3 r t over m and isolating m will have molar mass multiplied by v rms squared over 3r so let's plug in the given values here we know that the motor mass of helium gas is 4 grams per mole we need to convert grams to kilograms because we are using r which is in terms of joles and joles is kilogram meter squared per second squared.
01:06
So we need the mass in terms of kilograms.
01:09
And this is the conversion factor.
01:11
A thousand grams is one kilogram.
01:13
Now multiply vrms, that's 4 and 50, 450 meters per second...