Sound Waves Lab

These parts make up the sound waves and they travel through a medium which is the material that a wave energy travels through. On page 10 in Activity 2 we had to fill out the table on how to make a louder sound and we learned that to have a louder sound the compressions have to be larger and to increase the frequency the compressions also had to be larger. When we did the activity with the slinkies this was the case because when we had more compressions the sound was louder and the frequency increased. In Activity 1 on page 4 we learned that sound intensity is how much sound energy passes through a certain area in a certain amount of time as it spreads out from the source. Decibels are a unit of measure that indicates the relative intensity of a sound. In Activity 1 on page 5 when we were looking at the table it showed us that as the sound intensity increases the decibel increases because the decibel measured how intense the sound was. According to the chart on page 4 the decibels at a quiet library is 40 dB and the relative intensity is 1000, however if the noise source is some explosions then the decibels is 160 and the relative intensity is

These averages we determined from the trials can be compared to the accepted speed of sound (344.2 m/s in this specific temperature), and we determine the relative error percentages:

The sound waves are produced by a random oscillating crystal, and are inaudible to humans. A instrument called a

Both scientists made the prediction that if wasps were tested at a frequency of 42,000 Hz, the following outcome would be observed.

In longitudinal waves the object doesn’t exactly follow the waves fully instead the object moves in a back and forth motion while the waves continues to move forward through the object. While in transverse waves the object doesn’t follow the waves as well and just moves up and down in the same position.

The purpose of this experiment is to measure the speed of sound in air and to determine the effects of frequency on the speed of sound.

The main purpose of the lab is to study the two basic waves along with, their properties. The results we got were diverse from each other. The longitudinal waves compress than stretches to become a rarefaction. However, with the transverse waves, the medium was much slower when it was moving up and down. The only similarity that the waves share is that the energy travels through the slinky

-“The wave disturbance travels 300 m for each wavelength.” The speed of the wave does not determine how long the wave disturbance travels for each wavelength. We do not have enough information to determine that.

Ultrasonic sensors emit short, high-frequency sound pulses at regular intervals. These propagate in the air at the velocity of sound. If they strike an object, then they are reflected back as echo signals to the sensor, which itself computes the distance to the target based on the time-span between emitting the signal and receiving the echo.

Sound waves are nothing more than an energy transfer through a medium be it through a liquid, solid, or a gas. Sound pressure or intensity is measured on logarithmic scale in decibels dB which increases on an order of magnitude. For instance a quiet conversation would be around 30 dB and whereas the human pain threshold would be just over 100 dB. While the pitch or frequency of the sound is measured in hertz or Hz, the higher the hertz the higher the pitch of the sound and vice versa (Hildebrand, 2004).

According to Gill (2012,p. 11) the equation for Acoustic impedance is Z=ρc, where (Z=Acoustic impedance, ρ =density of medium and c =velocity of beam). From this equation is understood that acoustic

We had measured the speed of light going through the glass. 0.67c was the speed of light. The glasses density changed the wavelength of speed. The light going through an medium will increase when the density of a medium decreases. The opposite thing happens when you increase a medium’s density.

Have you ever wondered why glass bottles made a sound, kind of like a music note? Well, this paper will explain how this works. The paper will be talking about sound, sound waves, standing waves, musical note names and frequencies, resonance, and closed-end air columns. Closed-end air columns will be a main focus in the paper, studying the physics behind it. Glass bottles are an example of a closed-end air column. Therefore, the more water inside the bottle, the lower the note, and less water would be a higher note.

The red bar on the left acts as the driving piston. If it moves in a sinusoidal manner from left to right, then the wave that is produced will be a sinusoidal wave. Since the wave is sinusoidal, the wavelength, amplitude and frequency are constant. This is seen in nature as a tuning fork, which produces a periodic sound wave. In a one dimensional tube as shown above, each particle undergoes simple harmonic motion. The volume that is contained in one wavelength also undergoes this same motion. We can represent the displacement of this volume as:

To describe the concept of equal loudness regardless of frequency, the unit phon was developed. Each curve of the equal loudness contours defines a single phon level. For example, the curve that is 40 dB SPL at 1 kHz is defined as 40 phons; 40 phons at 10 kHz is therefore approximately 50 dB SPL and at 100 Hz slightly more than 60 dB SPL. Phons and decibels SPL are the same for a 1 kHz tone — an increase of 10 phons is equal to an increase of 10 dB at 1 kHz, but it may be more or less at other frequencies.