Lab Report Day 18 - Oscilloscope and Mystery Box

This is an oscilloscope. In the tube, a heated filament and a series of accelerating and focusing electrodes  serve as the source of a well-collimated beam of electrons, which cause a beam of light. 

This is the inside view of an oscilloscope. 

 Proof that Deflection is Proportional to Voltage

Some derivations for an electron traveling through two plates. 

Sounds from a Function Generator

This is a function generator. We are going to use it to generate several different waves. 

Professor Mason is showing us how a speaker works. 
To do this experiment, we first plug in and turn on the function generator.  We turn off the DC offset. We then connect the cable with the clip leads to the a low voltage output. We set the function generator to produce a 96-Hz sinusoidal wave by setting the frequency multiplier to 100 and adjusting the dial appropriately. Finally, we attach the two output clip leads from the function generator across a speaker.

Our set up for this experiment. 

From this experiment, we know that at 96 Hz, we only hear a low pitch constant sound. When we change the function of a wave,  we hear different sounds. Triangle is close to a sin function, while a square produces a loud constant sound. When we get a higher frequency, we get a high pitch sound. When the voltage gets higher, the volume also gets louder. 

Wave of the function as a sin function. 

Wave of the function as a square function. 

Wave of the function as a triangular function. 

We play with the oscilloscopes, the power controls the brightness. The focus controls the diameter of the light. 

Calculation of the period shown in the Oscilloscope: The frequency is calculated to be 92.5 Hz. It is close to the theoretical value. 

Different Shapes of AC power supply since the current is changing directions all the time, and the voltage is not constant. 

Different Shapes of AC power supply since the current is changing directions all the time, and the voltage is not constant. 

Different Shapes of AC power supply since the current is changing directions all the time, and the voltage is not constant. 

Different Shapes of AC power supply since the current is changing directions all the time, and the voltage is not constant. 

Different Shapes of AC power supply since the current is changing directions all the time, and the voltage is not constant. 


Mystery Box


After knowing the property of AC and DC and other components of the oscilloscope, we are going to measure a mystery box. This is how a mystery box looks like.

Example of how we measuring the voltage and whether it is AC or DC. 

 Using the oscilloscope, we can find the frequency, time and voltage. The value makes sense.  

 Results of a Mystery Box

Summary:

 In today's lab, we learn how to use a oscilloscope.