# Charles's Law Problem.

1. Oct 30, 2010

### lj19

QUESTION WITH GIVEN INFORMATION:
How would I solve this problem using Charles's Law?

V1=169-L. V2=85-L. T2=166c.

EQUATION:
Charles's Law is: V1/T1=V2/T2.

THE ATTEMPT AT A SOLUTION:
This problem is from an online homework source. I substituted the given information into the equation for Charles's Law: 169/x=85/166->85x=28054->x=330.

Last edited: Oct 30, 2010
2. Oct 30, 2010

### Staff: Mentor

What is T?

3. Oct 30, 2010

### lj19

T=temperature. V=volume.

4. Oct 30, 2010

### Staff: Mentor

What temperature?

5. Oct 30, 2010

### lj19

T is the symbol for temperature in equation for Charles's Law.

6. Oct 30, 2010

### Staff: Mentor

That's not what I am asking about. This is not "any" temperature. It has a specific name.

Check wikipedia article on Charles' law.

7. Oct 30, 2010

### lj19

For this class, I am supposed to know that T=temperature. In this problem, T1=unknown, and T2=166 Celsius.

8. Oct 30, 2010

### Staff: Mentor

No. Please read wikipedia article. Repeating the same wrong information won't get you to the right answer. There is something important that you are missing about the temperature.

9. Oct 30, 2010

### lj19

I have read the Wikipedia article on Charles's Law. The information provided on the article cannot be applied in this class for this problem, because I have not been taught absolute temperature, or other information from that article.
I understand how to solve this problem, as I provided under my attempts to solve it, but if I solve it using the equation for Charles's Law, the answer is not correct.

10. Oct 30, 2010

### Staff: Mentor

That only means you have been not paying attention during class. It is impossible to solve the question not using absolute temperature.

There are no different laws for different classes - physics laws are universal. They can be formulated in a slightly different way, but they are exactly the same.

Please check what is an absolute temperature scale unit, perhaps that will show you where is your mistake.

11. Oct 30, 2010

### lj19

This problem was one part of a three part problem. The other two problems were in the same format using Charles's Law, except with different numbers. I have not been taught absolute temperature. The problem can only be solved by using the givens and plugging them into the equation for Charles's Law, and then solving it, which I have done. I did the exact same thing with the other two problems, and they are correct.
Could someone please explain to me if when solving this problem, I need to convert 166 Celsius to Kelvin's to Celsius? The final answer is in Celsius.

12. Oct 30, 2010

### Staff: Mentor

You need to use absolute temperature. Absolute temperature is the one measured in Kelvins. So yes, you have to convert to Kelvins first, do the calculations using Kelvins (because Charles' law requires absolute temperature), then convert back to Celsius.

If you were not so stubborn in repeating the same wrong information again and again you would finish solving this question long ago.