Friday, January 13, 2017

Blog 1 Group 1

Scout Case and Austin Kane

1.  What is the class format?
Monday: Quiz discussion for 15 minutes, then lab intro, then lab for the rest of class.
Wednesday: Finish up the lab.
Friday: Comment and discuss the blogs.
Nonclass days: Work on blogs and comment on others.
-The class is out of 1000 total points which are received through; Quizzes, blog reports, blog discussion, final project, midterm exams, and final exams.

2.  Important safety rules:
-Know where fire extinguisher, first aid kit, telephone, and emergency numbers are located.
-Check equipment to make sure it isn't defective.
-Keep things clean.
-When not using equipment turn it off.
-Make sure equipment with electricity is grounded.
-Keep hands dry.

3.  Does current kill?
Yes, if the current is between .1 and .2 mA it will kill you. If it is just above or below it can cause horrific pain, lungs to shut down, and also burns.

4. How to read color coding on a resistor:

5.  The tolerance is the percentage of error in the resistor's resistance. An example in the experiment that we conducted was that each resistor contained a band on the end that was either gold or silver.  Gold was a 5% tolerance, and silver is a 10% tolerance.

6.  Prove all the resistors are within the tolerance range:
Color Band Resistance(Ω)  Tested Resistance (Ω) Tolerance Range (±5%) 
2.2 (kΩ) 2.174  (kΩ) 2.09-2.31  (kΩ)
390 388 370.5-409.5
175 175.8 166.25-183.75
272 270.8 258.4-285.6
150 148 142.5-157.5
151 150.1 143.45-158.55
270 269.5 256.5-283.5
202 202.2 191.9-212.1
201 200.9 190.95-211.05
681 680 646.95-715.05
The values obtained from doing the tests all fall within the tolerance range of 5%.
The range is the max and min that the tolerance would allow.

7.  What is the difference between measuring the voltage and current using a DMM? why?
When you are measuring voltage, you have to have the DMM in parallel with the circuit.  When you are measuring current you have to have the DMM in series with the component you want to measure the current through. This requires you to break the circuit for measuring current.

8.  How many different voltage values can you get from the power supply? Can each one of them be changed to any value?
There are 3 different voltage values you can obtain from the power supply.  Two of them you can change from 0-25 volts and the third value is a fixed value of 5 Volts.

9.  Practice Circuit Results:
Voltage Drop: 5.36 V
Current through the Resistor: 61.2 mA
Resistance: V=I*R so 5.36 V =  .0612 A * R, R=87.58 Ω

Doing the process of working the circuit to test for the current and the voltage.

The Circuit board used to test the resistor.

10. How do you experimentally prove Ohm’s Law? Provide measurement results. Compare calculated and measured voltage, current, and resistance values. 
You experimentally prove Ohms law by recording the voltage and current at different levels of each, once you do those you can solve for the resistance.  The values obtained should come back very close to the actually given resistance. 

Trial 1: 83 Ohm Resistor
Volts (V) Current (A) Resistance (Ω)
5 0.0612 87
7.95 0.0912 87
10.3 0.1206 85.406
12.75 0.152 83.88
15.2 0.189 84.2
Trial 2: 53 Ohm Resistor:
Volts (V) Current (A) Resistance (Ω)
1.11 0.026 42.69
2.209 0.0412 53.616
3.5 0.0656 53.35
4.3 0.0804 53.482
5.34 0.1002 53.29

Testing Results for Circuits and Currents:

11. Rube Goldberg Circuit:

12. Circuit diagram for the Rube Goldberg setup:

13. We could have an L.E.D. that is triggered causing the photo resistor to activate which would spin the motor causing it to wind up string moving a bar which was blocking a ball which could then go trigger another Rube Goldberg set up

Displaying 20170117_141248.jpg


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  2. On question number 6, your color band resistance numbers do not account for them being Ohms of kilo-Ohms (i.e. 2.2). Also your tolerance range column is confusing, not sure what it is showing. Check grammar on problem 7. Well done on the rest.

  3. Did you have any trouble when building the Rube Goldberg circuit? Transistors can be tricky to work with, and we had an issue where the photo-resistor was not working properly with the circuit. The DC motor was always on.

    You mention that safety procedure is to make sure that the equipment is not defective. As a beginner in building circuits I personally would not blame a component for the circuit not working. I would more than likely blame myself for the result of the circuit not working.

  4. On your Rube Goldberg circuit, did you try shining your phone flash light on the transistor and seeing how fast the fan moves? It moves quite fast! Also instead of the fan if you use a light it will shine super bright when you shine your flash light on it! :)

  5. Good blog. I like your Ohm's Law table. Do not forget to respond to other comments next time.
    - #13: picture not there.
    - Some captions missing.