4. Discussion

4.1 Key findings & Analysis of results


The speed of the microwaves was calculated by multiplying the average wavelength determined from the hot spots of each food and the frequency of the microwave oven. Since microwaves and visible light are both electromagnetic waves, they have the same speed.


Error analysis is a set of techniques for dealing with errors that may occur due to human or systematic errors. (T. John, 1997)  In science, the word "error" does not take the usual meaning of "mistake". Instead, it is often used interchangeably with "uncertainty" when referring to the result of a measurement. (T. John, 1997) According to sciencefair.math.iit.edu (2017), all scientific reports must contain a section for error analysis. The purpose of this is to reason out how and why the results deviate from the expectations. (sciencefair.math.iit.edu, 2017) Error analysis should include a calculation of how much the results vary from expectations. (sciencefair.math.iit.edu, 2017) This can be done by calculating the percent error observed in the experiment. (sciencefair.math.iit.edu, 2017) Thus, we shall be including an error margin in our experiments.


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Figure 1: Table of results from egg experiment


After obtaining our measurements, we proceeded to measure the speed of light using the following steps: (Screenshot from Project Report attached as Blogger does not support equations)


When using the formula and results from the egg whites, the average speed of light from the five tests was calculated to be 300,860,000 m/s, which is  a 0.356% error margin, which is quite little when compared to the actual speed of light, 299,792,458 m/s. Chocolates were unable to produce substantial results. We were not able to do the marshmallow experiments due to the marshmallows not being Halal. More about this in Section 4.4.


4.2 Explanation of key findings


By removing the rotating platter in a microwave oven, hot spots were produced which are the antinodes that form when the microwaves reflect off the walls of the oven and interfere with each other, producing standing waves. The distance between the hot spots did not depend on the type of food tested, but the egg whites gave the best results because their hot spots had a more defined centre making it easier to measure the distance between them.


4.3 Evaluation of Hypothesis


Thus, our hypothesis was true as we were able to measure the speed of light approximately using a microwave. We also got less than a 1% margin error while we were doing the egg experiment.


4.4 Limitations and Areas for improvement


We had a few limitations, such as the fact that the microwave we used was only meant to be used for Halal food. Thus, our experiment using marshmallows got scrapped due to the marshmallow’s use of pork gelatin in the ingredients list, thus making it non-Halal. During our chocolate experiment, we realised that we left the chocolate in the fridge and the timing to melt varied with each experiment. However, when we were doing the chocolate experiment, we were unable to see any melted spots. Instead, the whole chocolate melted, like what can be viewed in the next photo. This was the best, however still inconclusive, result we were able to get throughout the chocolate experiment.



Thus, our experiment with the chocolate failed as we were unable to get proper results.

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