5/5 week 11 day 1 Oscilloscopes and Mystery Box

At the beginning of the class, the professor shows us  the electron gun.  The electron gun is an electrical component in some vacuum tubes that produces a narrow, collimated electron beam that has a precise kinetic energy. 
When it is charged, we can see the bright point in the second photo.

 This is a simple graph of the electron gun. at first, the electron has different directions. when the electrons go through the 4 pieces of sild, these silds can accelerate electrons and change their directions.

 Then in this video, the professor shows us an oscilloscope. it can produce the wave, but the wave is always in one direction. 

in this photo, we draw and predict the graph of the wave. Because it is only from left to right and has one direction, so we draw it in this photo.

 Then the professor add a battery on the oscilloscope and we find that the voltage is bigger. 

in this photo, we figure out the motion of electrons in electron gun. 
for a, we find the force of electron is F=Eq=Uq/d
for b, we can find the acceleration is a =F/m=Uq/dm
for c, we draw the graph of motion
for d, we find the time to get to the upper side when the electron has a distance of d from upper side, t=L/v0x
for e, we find the velocity of y-axis when the electron gets to the upper side. vy=at=Uql/dmv0x
Then in this photo, we also figure out the distance when the electron leaves the sides and gets to the wall. we know the distance between the side and wall is D and the stright distance y=vyt=UqlD/dmv0x^2

Then we set up the equipments in this photo, we use one function generator, one samll speaker and 1 BNC to clip lead cable 

First, we do the activities at the bottom of this photo. 

In this photo, we aswers the 4 questions in the activity.

then we did the activity about oscilloscope. we answer the 5 questions in the second photo.

Then we begin to do the activity about measuring wave forms.

in this photo, we answer the 4 quesions of this activity.

these two photos are the answers of d, the first one is sinusodial wave and the second one is square wave.

in these two photos, we start to do the tasks No.1 , the first one is we connect a small DC wallwart to the oscilloscope and we measure the voltage is 5V and the frequency is 60Hz. The second photo is that there is a noise.

 In this photo, we connect an AC transformer to the input of the oscilloscope and measure the output.

Then we begin to do the mastery box activity.

We connect the blue one and it is DC and we find that the voltage is 5V

then we connect the yellow one, but nothing happens

we connect the green one and it is DC and it is 8.5V 

in this photo, the red one is AC one.

in this photo, we make a graph of all 4 different colors.

Conclusion:

In today’s class, we learned how to use the oscilloscope. We use different electronics to measure and visualize voltage changes. We learned to how to observant and to manipulate the settings on the machine to reveal the true wave patterns on screen. We learned many things about frequency and DC/AC circuits when connecting them to the oscilloscope. We find to use oscilloscopes in order to see voltage changes and use a simple amplifier to look at how analog electronics are used as a conversion to boost a weak signal into a sound we can hear