Thermal Expansion of a Solid

In summary, there is no significant difference in using kelvins or celsius for temperature measurements in equations, as long as changes in temperature are being considered. This is because both units can be easily converted to each other. However, there may be a small error in the calculations due to the conversion.
  • #1
BioCore

Homework Statement


Usually when temperatures are written as "T", they are given in kelvins and when written in "t" they are given in celsius. The equation dL = aLdT used T for temperature yet, in the experiment temperature is measured as celsius. Is there any difference? Why?


Homework Equations


dL = aLdT

where a is coefficient of Linear Expression


The Attempt at a Solution



This is just an experiment preparatory question. I was not sure about this but my answer would be that there is no large difference as we all know the equation:

Kelvins = Celsius + 273

Although since there is always a reading error with even temperature then the conversion would also accompany a calculated error. Although I am unsure. Could someone direct me to the right direction or just confirm that I am correct?
 
Physics news on Phys.org
  • #2
I wouldn't rely on t vs T - it's not necessarily widespread.

If you are talking about changes in temperature it doesn't matter. Similairly any equations involving simply adding or subtracting a temperature works for celcius or kelvin. It's fairly easy to show this with some algebra.

I'm not sure what question you are asking.
The error in the change in length will be the same percentage as the error in the measurement of temperature. It's easy to show this by calculating the answer for a particlular dT and then for dT+(some small increment) and comparing the dL.
 
  • #3
Well I have to do an experiment, and in the experiment I will measure temperature using a thermometer in celsius. Now since the equation at the top though uses Kelvins for temperature and not celsius, does it make any difference in measuring with celsius and not kelvins?

From your answer, I understood that since we are taking the difference there is no problem.
I seem to have forgotten that little point somehow, I believe that would be a good enough answer seeing as the difference in kelvins or celsius would be the same.
 
  • #4
Correct it's very easy to prove, imagine making a cup of coffee!

t1 = 17C = (273 + 17) K
t2 = 100C = (273 +100) K

dT = t2-t1 = (273 + 100) - (273+17) = (273-273) + (100-17) = 83
So it really doesn't matter about the 273!
 
  • #5
Thank you for the help mgb.
 

1. What is thermal expansion of a solid?

Thermal expansion of a solid is the phenomenon where a solid material expands or contracts in response to changes in temperature. This occurs because as the temperature increases, the particles in the solid gain energy and vibrate more, causing the solid to expand. Conversely, as the temperature decreases, the particles lose energy and vibrate less, causing the solid to contract.

2. What factors affect thermal expansion of a solid?

The main factors that affect thermal expansion of a solid are the type of material, the initial temperature of the material, and the change in temperature. Different materials have different coefficients of thermal expansion, meaning they will expand or contract at different rates. The initial temperature of the material also plays a role, as materials that are already at a high temperature will have less thermal expansion compared to materials at a lower temperature. Lastly, the greater the change in temperature, the greater the thermal expansion will be.

3. How is thermal expansion of a solid measured?

Thermal expansion of a solid is typically measured using a device called a dilatometer. This instrument measures the change in length or volume of a material as it is heated or cooled. The results of these measurements are used to calculate the coefficient of thermal expansion for a particular material.

4. How does thermal expansion of a solid affect everyday objects?

Thermal expansion of a solid can have a significant impact on everyday objects. For example, bridges and railroad tracks are designed with expansion joints to allow for the expansion and contraction of the materials due to changes in temperature. Without these joints, the materials could buckle or break. Additionally, household items such as metal cookware and glass containers can crack or shatter if exposed to sudden changes in temperature due to thermal expansion.

5. Can thermal expansion of a solid be controlled?

Yes, thermal expansion of a solid can be controlled through the use of materials with lower coefficients of thermal expansion, such as certain types of alloys or composites. It can also be controlled through the design of structures, such as using expansion joints or incorporating flexible materials. In some cases, heating or cooling the material before use can also help minimize the effects of thermal expansion.

Similar threads

Thermal expansion of square from temperature increase of 50K
    • Introductory Physics Homework Help
Replies
28
Views
1K
Density of a solid and Clapeyron equation
    • Introductory Physics Homework Help
Replies
7
Views
1K
Help with Thermodynamics process equations and units
    • Introductory Physics Homework Help
Replies
11
Views
836
JEE solution wrong? (tempco of a clock)
    • Introductory Physics Homework Help
Replies
14
Views
484
When to convert units of temperature?
    • Introductory Physics Homework Help
Replies
2
Views
1K
Rate of Energy Transferred, Aluminum Pot
    • Introductory Physics Homework Help
Replies
5
Views
1K
Troubleshooting Interplanetary Cruise Calculations
    • Introductory Physics Homework Help
2
Replies
41
Views
4K
Stress in cylinders due to thermal expansion
    • Mechanical Engineering
Replies
16
Views
481
Adiabatic expansion problems
    • Introductory Physics Homework Help
Replies
5
Views
2K
Thermodynamics (Heat expansivity)
    • Introductory Physics Homework Help
Replies
4
Views
1K

Hot Threads

Recent Insights

Back
Top