Why Am I Struggling with Thermal Physics Calculations?

[Confuzzled_VN]

Hi..i was trying out some calculations i found on some site as practice for my exam this Friday and realized that i don't understand at all..
Everytime i tried something..my answers were wrong..

E.i

1. How much heat energy is needed to heat 4 kg of aluminium by 8 (degrees)C?

The answer:

1. Energy = mC(delta)θ = 4 x 1200 x 8 = 38400 J

I don't understand where the 1200 came from..

Can anybody give me links to thermal physics and general physics notes and/or worked examples for me to try out?

 

[Astronuc]

It would help if one would write units with the numbers in a problem.


Energy = mC(delta)θ, where m is the mass (in this case 4 kg), C is specific heat (which is unique or specific to a material which would be in units of J/kg-K), and θ would be the temperature (in K or °C, and not to be confuse with an angle). Some people use T for temperature.


Here is a good site for some basic physics - http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html

and for the problem at hand - http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/spht.html

Table of specific heats - http://hyperphysics.phy-astr.gsu.edu/hbase/tables/sphtt.html#c1
C_p = 900 J/kg-K for Al in this table.


Please expend some effort and review the notes on Hyperphysics.

Thank you.

 

[Moetasim]

Hi there,

It sounds like you are struggling with thermal physics calculations and are looking for some resources to help you understand the concepts better. That's great that you are practicing for your exam, but it's important to first have a solid understanding of the fundamentals before attempting calculations.

To answer your question, the number 1200 comes from the specific heat capacity of aluminum, which is 1200 J/kgK. This value represents the amount of energy needed to raise the temperature of 1 kg of aluminum by 1 degree Kelvin. In your calculation, you are multiplying the mass (4 kg) by the specific heat capacity (1200 J/kgK) and the change in temperature (8 degrees) to get the total energy needed (38400 J).

As for resources, there are many websites and textbooks that offer thermal physics notes and worked examples. A quick Google search for "thermal physics notes" or "thermal physics examples" should yield plenty of results. I also recommend checking out your school's library for textbooks on the subject.

In addition, it may be helpful to reach out to your teacher or a classmate for extra help and clarification on the concepts. Don't be afraid to ask questions and seek out additional resources to improve your understanding. Best of luck on your exam!

 

[baba89]

I can understand your frustration with not understanding thermal physics calculations. It can be a complex subject, but with practice and understanding of the underlying principles, you can improve your skills in this area.

Firstly, let's address the specific calculation you mentioned. In this case, the value of 1200 represents the specific heat capacity of aluminum, which is the amount of energy required to raise the temperature of 1 kg of aluminum by 1 degree Celsius. This value is a constant and can be found in thermal physics tables or textbooks.

To improve your understanding of thermal physics, I would recommend studying the fundamental principles such as heat transfer, thermodynamics, and thermal equilibrium. This will provide you with a solid foundation to approach more complex calculations.

Additionally, practicing with different examples and problems can also help improve your skills. There are many resources available online, such as physics forums, tutorial websites, and YouTube channels that provide worked examples and practice problems. I would suggest looking for resources from reputable sources, such as universities or educational institutions, to ensure the accuracy of the information.

In conclusion, don't get discouraged if you don't understand a particular calculation at first. Keep practicing and seeking out resources to deepen your understanding of thermal physics. With determination and effort, you will be able to master this subject and excel in your exam. Good luck!