#2 AC vs DC [Post Homework Here]

[ThePyroElectro]

A new lesson was posted today:
http://www.pyroelectro.com/edu/analog/ac_vs_dc/

Post your homework answers here to compare with everyone else!

[Lezarkween]

Hello !

I'm not actually posting an answer, but a question. I have stripped off what I thought was the right cable, but I guess I got it wrong because here is what was inside.



Can You tell me what cable I should take ?

[ThePyroElectro]

Hello !

I'm not actually posting an answer, but a question. I have stripped off what I thought was the right cable, but I guess I got it wrong because here is what was inside.



Can You tell me what cable I should take ?

Hello,

What you have there looks more like a headphone set for a cell-phone. You can still use this for the course, but the wire is very thin so it might be difficult getting it into a breadboard.



The best thing to do, if you have a soldering iron, is to solder a little bit onto each wire. This will add some tin to them and make them more sturdy for use with a breadboard.

Alternatively you can go to the store and get a 'stereo cable' like this one and cut off the end, the wire inside should be a little thicker than your headphone set.

But you should try using the headphone set first, as it should work with all the experiments in this course.

Good luck!

[wr9h]

Homework Lesson 2 AC/DC

Q1) DC electricity is a stable non varying form. When graphed as voltage versus time the voltage will be a constant value. AC is a varying form of electricity. When graphed as voltage versus time AC voltage will rise above (positive) zero volts and fall below zero (negative) volts. The number of positive/negative alternations in a second is called the AC frequency.

Q2) We can change or vary three things to convey "something" with an AC voltage:
a) Amplitude (distance above and below zero volts)
b) Frequency (one positive with one negative alternation is one cycle. If this cycle occurs 60 times
a second the frequency is 60Hz)
c) Phase (or form) (example:keep all alternations above zero volts for a period of time)

Q3) An O'scope allows us to actually see the AC signal! (Could be used to see a varying DC signal used in digital electronics)

Q4) The voltage from a fully charged battery will be a constant value, say, 9 volts (although the ones I used for the Wien oscillator circuit were 9.3 volts....). The voltage from a home outlet varies between +125 volts to -125 volts 60 times a second (60Hz).

[ThePyroElectro]

Homework Lesson 2 AC/DC

Good answers! All correct.