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#1 Help Me ! » Boolean rule #11 » 2013-01-20 09:34:01

reallylongnickname
Replies: 2

This is Boolean rule#11. (It is not complete I know). My Q is, how did the 

develop in the equation in line 4?

 
     rule #10 A = A + AB
     rule #  7 A = AA

#3 Help Me ! » distributive law » 2012-10-24 06:22:42

reallylongnickname
Replies: 1

The way to solve this is apparently to use division by the common factor which is 3x^2

However, if I solve it with out the division like this (see below), I get the same answer. So what rule should I be following? Am I skipping steps or am I using different method?

#4 Help Me ! » avg value » 2012-09-11 14:16:28

reallylongnickname
Replies: 0

avgvalue.gif

The question asks, what is the average value of the output voltage fro the circuit.
The choices are; 5.48v 2.74v 0v and 6.37v
I choose 6.37v using a simple formula; 2(160)/pie then divid by 16. Also tried accounting for .7v through diode, however, the book says the answer is 5.48v. Could the book have made an error with their answer?

#5 Re: Help Me ! » correct? » 2012-07-21 11:11:41

Yes,  this is what I mean... I kept coming up with a different answer than the text book.  19.6 * 10^-6

#6 Help Me ! » correct? » 2012-07-21 07:44:06

reallylongnickname
Replies: 4

Here is a question example out of text. Is the area correct? (I wasn't able to fill in the formula because of latex errors).

"What is the inductance of a 2 cm long, 150 turn coil wrapped on an low carbon steel core that is 0.5 cm diameter? The permeability of low carbon steel is 2.5 x10-4 H/m (Wb/At-m)."


#7 Help Me ! » RC circuit » 2012-07-05 13:12:31

reallylongnickname
Replies: 1

rccircuit-4.png

should be the formula to solve the series part, but how to solve the parallel R2 with Xc2?

#9 Re: Help Me ! » ωτ∫ » 2012-06-24 16:46:10

Ok thats true. I think the idea is that once switched to #2, Vs is shut off. What time is taken to discharge the capacitor? I guessing just the t=RV formula could be used.

#10 Re: Help Me ! » ωτ∫ » 2012-06-24 16:14:24

Based on electron flow (neg to pos) current is flowing.

#11 Help Me ! » ωτ∫ » 2012-06-24 16:02:50

reallylongnickname
Replies: 4

rccircuit.jpg

Lets say the swich is moved to #2 position instead of #1.
I cannot figure out what is happening with the current in this RC circuit. Im guessing current would start from VS to R3 then to R2.

#12 Re: Help Me ! » Top bottom Bottom top » 2012-06-23 08:43:14

Came up with the idea to substitute  "t"  with "equivalent". This will also avoid any confusion with the resistance total of the circuit when working with series-parallel circuit.

#13 Help Me ! » Top bottom Bottom top » 2012-06-23 06:10:15

reallylongnickname
Replies: 3

Is there a trick to keep from confusing the

in the numerator and the denominator for each formula? 


Voltage divider formula in series.




Current divider formula in parallel.     

#14 Re: Help Me ! » exponents and yx » 2012-06-18 16:17:38

I can put calc into rad mode, but still not sure how to compute the formula. What is to be inputted for "rad" in the formula?

#15 Re: Help Me ! » exponents and yx » 2012-06-17 13:31:06

Thx, it is more clear now.

Here is a separate Q.
I want to type in this angular formula on calculator. How do I go about inputing "rad?"

#16 Re: Help Me ! » exponents and yx » 2012-06-16 14:05:49

I keep making conversion errors. I can understand why it doesn't work on calculator if u go; 1 divide 10 times 10 yx -3
Why do you have to go; 1 divide 10 exp-3 to get the the answer in proper units.

#17 Re: Help Me ! » exponents and yx » 2012-06-16 12:22:11

The -3 is exponent.

If I go; 10 * 10^1 = 100
If I go; 10 exp 1 =100

#18 Help Me ! » exponents and yx » 2012-06-16 11:28:16

reallylongnickname
Replies: 8

I thought yx and exp were the same thing.
10 yx 1 = 10 on calculator but 10 exp 1 = 100

#19 Re: Help Me ! » simplify expression » 2012-06-06 15:22:53

Never mind, I solved it. It is now correct

#24 Re: Help Me ! » V/r = I » 2012-05-26 05:30:51





If I use the full method, I get the correct answer but this seems long process.

#25 Re: Help Me ! » V/r = I » 2012-05-26 04:56:02

Sorry, I added this to the original post before your reply:
My method is this: Divide the numbers first, then move the decimal three steps to the right in order to convert to milli amps. What rule am I not following in mathematics?

Yes 1000 ohms resistor or 1K.

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