Abstract
The purpose of this lab was to explore the nature of waves by determining the properties of different transverse waves. This was done my measuring certain properties (amplitude, wavelength and period) and then using those values to calculate other properties (frequency and wave speed) of each wave.
Introduction
In this experiment a slinky was used to create two different transverse ways, which were then analysed and the properties of each wave was determined. The properties of the transverse waves that were easily measured include; the amplitude (m), wavelength (m) and the period (s), and the properties that were later calculated include; the frequency (Hz) and the wave speed (m/s). To measure these properties a ruler and a measuring tape were used, as well as a stop watch and a slow motion camera.
The waves that were created in this lab are referred to as mechanical waves which are waves that need a medium to travel through. Some other examples include longitudinal, surface and torsional. Each type of mechanical wave has various characteristics, and those for transverse waves include a cycle (one complete repetition of the wave), period (T, in s, the time it takes for one cycle), amplitude (A, in m, maximum displacement from the rest point), frequency (ƒ, in Hz, the number of cycles per second), and wavelength (λ, in m, the length of one cycle). Transverse waves also have a crest (the highest point of the wave), a rest position (the median point) and a trough (the lowest point).
Hypothesis
If tools such as; a ruler, a measuring tape, a stop watch and a slow motion camera are used, the properties of two different transverse waves can be determined and calculated.
Materials
Method
A tape measurer was stretched to 3 meters and then taped to the ground. Then a meter stick was placed perpendicularly in the middle of the tape measurer, with 50 centimeters of the meter stick above the tape measurer and 50 centimeters below. First two experimenters moved the slinky to create a transverse wave, while the other experimenter collected data by recording the wave on a slow motion camera, as well as a stop watch. This procedure was repeated again but with the two experimenters creating a different transverse wave using the same slinky. The video footage was analysed and all data that was derived from the video was recorded in that table below. Finally the properties that are not easily measured, are calculated using the equations below and also added to the data table.
Equations
Data
Calculations
Wave #1
Wave #2
discussion
The purpose of this lab was to explore the nature of waves my determining the properties of two different transverse waves. After using simple tools to simply measure the wavelength, amplitude and period, those values were then used to calculate the final properties of the wave; frequency and wave speed. The hypothesis of this lab that was stated at the beginning was proven to be true, as all of the properties of both transverse ways were determined. Most aspects of this lab were expected however there were some things that were unexpected. For instance, it was predicted that one would be able to determine all the properties of each wave, however how the two wave's values differed from each other was unexpected. Because while the creating of the waves was in process from a naked eye perspective one would think that they aren't that different from each other, as it is the same slinky and they waves don't seem to by varied that much. However, after calculating the properties of each wave it became obvious that they were in fact quite different. For example it was predicted that the wavelengths would be closer in value, however wave #1 had a wavelength of 1.4 meters and wave #2 had a wavelength of 2.7 meters, which is almost twice as much as the wave #1. Also the wave speed was unexpected, as though one could notice that obviously wave #2 was faster than the other however the calculated range was not expected.
Sources of error
There were a few experimental error that occurred during this lab that could have effected the data and therefore changing the final results. The experimenters chose probably not the most accurate method of measuring the wavelength and amplitude. Because it was too difficult to just accurately see where the slinky was crossing with the meter stick and measuring tape, the experimenters decided to use a slow motion camera so that they could later analysis the footage. However the numbers on the measuring devices were quite difficult to read and therefore the values that were used to calculate was neither precise or accurate to the true value. Another source of error was the consistency in the man made wave. Because two experimenters were creating the wave with a slinky it is difficult to ensure that the properties of the wave are remaining consistent throughout the recording and measuring time. Perhaps in one video the transverse wave had a larger wavelength in one moment then it did the next, therefore making it inconsistent. Both of these sources of error, influence the validity of the the experiment.
Further research
To further research the topic of determining whether or not properties of waves can be found and calculated, perhaps a similar experiment could be conducted however on a larger scale. Increasing the size of the experiment could potentially impact the results and therefore it may be interesting to analysis how to the experiments compare. Another way to further research would be trying the experiment on different types of waves rather than just varying sizes of transverse waves. Perhaps all the properties of longitudinal waves can not be determined using just simple measuring tools.