Trend of Electromagnetic Temperature

[Da Apprentice]

In order to determine the temperature that an electromagnet reached after a 3 minute period the electromagnet was placed in a constant volume of water. After 3 minutes the change in temperature of the water was measured and from this using the equation Q=mcΔT the energy in joules transferred was calculated. This same process was repeated for the same electromagnet functioning at a different voltage. Graphing the joules exchanged for each experiment against the voltage that the electromagnet was run at produced what appears to be a linear trend.

Why this trend occurred is unknown. It was thought that the trend would be parabolic due to the following;

Joule's First Law: Q=k*I²*R

Ohms Law: V=I*R (hence I=V/R)

Substitution gives: Q=(k*V²)/R

I'm not sure if joules law is the correct law to use in this case and so this is most likely why I'm wrong. Can anyone explain why the result would be linear or confirm that it should in fact have been parabolic.

Thanks
Z.C

 

[cjl]

Did you only run 2 trials? You won't be able to determine whether the trend is linear or not without more data points.

 

[Da Apprentice]

no in total we ran the experiment at 6 different voltages and an additional point was assumed (at 0,0) because with no voltage the magnet doesn't increase in temperature and therefore no energy would be exchanged between the two.

The graph is attached.

Thanks for the reply.

Z.C.

 

[256bits]

Well, to start off how did you determine that a line of the one you have drawn is the best fit for your date points?
For each voltage setting, one would do several runs to have multiple data points.

You have several sources of error to begin with.
There is the experimental temperature difference between initial and final - and you do not say whether all runs of the experiment started at the same initial water temperature.
Also there is the voltage setting error.
And of course the mass of the water.

Calculating Q, by only using the increase in temperature of the water does not allow for the temperature increase of your electromagnet nor any heat lost from the water to the environment.

 

[sardar]

.

I would like to congratulate you on your experiment and the data analysis you have conducted. It is clear that you have put a lot of effort into understanding the relationship between voltage, energy transfer, and temperature change in an electromagnet.

Based on the information provided, it seems that the trend of electromagnetic temperature is linear. This means that as the voltage increases, the amount of energy transferred also increases in a linear fashion. This is consistent with the equation Q=mcΔT, where the change in temperature (ΔT) is directly proportional to the energy transferred (Q). In this case, the voltage serves as a control variable, and the relationship between voltage and energy transfer is linear.

It is important to note that the linear trend observed in your experiment may be influenced by several factors, such as the type and size of the electromagnet, the properties of the water used, and the accuracy of the measurement equipment. These factors may have contributed to the deviation from the expected parabolic trend based on Joule's Law and Ohm's Law.

Additionally, Joule's Law and Ohm's Law may not fully apply in this situation, as they were developed for resistive circuits and may not fully account for the complexities of an electromagnet. It is possible that other factors, such as the magnetic field strength and the efficiency of the electromagnet, may also play a role in the energy transfer and temperature change.

In conclusion, the linear trend observed in your experiment is a valid result, and it is important to consider the limitations and potential influencing factors when interpreting the data. Further research and experimentation may be necessary to fully understand the relationship between voltage, energy transfer, and temperature change in an electromagnet.