What Affects the RMS Speed Difference Between Helium Atoms and Molecules?

AI Thread Summary
The discussion focuses on calculating the new pressure of helium after its root mean square (rms) speed increases by 50% due to added heat. It highlights the relevant equation for rms speed, which is dependent on temperature and mass. A key point of confusion arises regarding whether the rms speed of helium atoms differs from that of helium molecules, with clarification that helium is a monatomic gas, thus the rms speed for both is the same. The mass of a helium atom is noted as 6.6x10^-26 kg, which is essential for calculations. Understanding these concepts is crucial for solving the homework problem effectively.
barrylwires
Messages
4
Reaction score
0

Homework Statement


Heat is added until the rms speed of a helium atom has increased 50%. Find new pressure. (Not all parameters given.)


Homework Equations


rms = (3kT/m)1/2
mass of molecule = mass of mole/NA
Then, mass of helium molecule is 6.6x10-26kg

The Attempt at a Solution


Question: Is rms speed of a helium molecule the same as the rms speed of an atom. Yes, because the atoms make up the molecule? No, helium is diatomic (right?) and so that has to be taken into account??
 
Physics news on Phys.org

Thread 'Errors and significant figures'

I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
View full post »
Thread 'Collision of a bullet on a rod-string system: query'

Thread 'Collision of a bullet on a rod-string system: query'

In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
View full post »
Thread 'A cylinder connected to a hanging mass'

Thread 'A cylinder connected to a hanging mass'

Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
View full post »

Similar threads

Calculating RMS Speed of Helium & Oxygen Gas at 260K
Replies
6
Views
5K
Help with rms speed of gas when molecules are doubled
Replies
1
Views
5K
Ratio between molecules having different speeds
Replies
2
Views
1K
Why Is There Little Helium in Earth's Atmosphere?
Replies
5
Views
2K
Does Doubling Gas Molecules Affect RMS Speed?
Replies
1
Views
4K
How Does Temperature Affect the RMS Speed of Helium Atoms?
Replies
1
Views
9K
Calculating RMS Speed of Molecules in a Compressed Gas
Replies
10
Views
10K
Thermodynamic Homework Problem Check
Replies
2
Views
2K
Thermodynamics: RMS Speed of Molecules
Replies
3
Views
20K
Calculating temperature from molecular speed distribution
Replies
10
Views
5K

Hot Threads

Recent Insights

Back
Top