Shock Value B/Circuit Lab C Question Marathon

[iwonder]

Nice pic.

Soo... Let's see if we can get someone else into this.

3 3 ohm resistors are in parallel and connected to a 5v battery. A fuse is in the battery that is rated for 4A. Will the fuse blow?

[FawnOnyx]

Alright fine I'll answer this one xD (Click to Show Hidden Text)

Three 3 ohm resistors in parallel is 1/3 + 1/3 + 1/3 = 1/Req, so the equivalent resistance is 1 ohm. Ohm's law gives I = V/R = 5v/1ohm = 5 amps. Therefore the fuse will blow.

[iwonder]

Awesome your turn!

[FawnOnyx]

Wanted to do some logic gates since they sound interesting:



1. What will the output be if A is true and B,C, D are false?
2. What will the output be if A and B are false and C and D are true?
3. What will the output be if A,B,C, and D are all false?

Bonus: write a boolean algebra expression for the output in terms of A, B, C, and D
Not worth your time: make a truth table for this gate system

Disclaimer: I just looked up logic gates for the first time so I'm not sure if these questions are 100% legit.

[TwelveSquared]

Ok, I waited since I virtually alternated answering every other question so far, but I'll go ahead.
I'm a programmer, so I can hopefully handle logic...
(although, i will note that i think the rules only cover DC, not digital logic. But it's still good practice anyway.)

These comparisons are what run your computer... (Click to Show Hidden Text)

Note: Since this is electronics, "true" is usually represented digitally as a 1 (or a high voltage, usually 5V), and false is 0(low voltage, usually 0V), which is what I'll use for the rest of this.
Problem 1:
Since A is high, the OR gate outputs high(1). Since both inputs in the NAND are low(0), it also outputs 1. These two bits are put into a  NOR gate, resulting in 0.
Problem 2:
A and B are false, OR gate outputs 0. same output for the NAND. Since both inputs are 0, the NOR outputs 1, the total output.
Problem 3:
OR gate has same situation, outputs 0. the NAND outputs 1, when put through the NOR results in 0.
Boolean expression:
(I had to look this up...)
_____________ 
``````````__
(A + B)   +  (CD)
EDIT: Ignore all the ````. The site removed the whitespace when i tried to do it with spaces. The two lines represent NOT(inversion).

[FawnOnyx]

Nice answer, looks right to me! Yeah writing boolean algebra on here isn't the easiest thing I guess.

I believe digital logic is a new theoretical topic this year, introduced in rule 3.d?

[iwonder]

Yup. Boolean logic is new this year, limited to the exam portion of the event.

[TwelveSquared]

Yup. Boolean logic is new this year, limited to the exam portion of the event.

Sweet!
(I will post the new question tomorrow, its already 10 where I'm at)

[TwelveSquared]

Alright, let's try this:
draw/CAD/etc. a Wheatstone bridge. Then state the equation used to find the resistance of an unknown resistor using it.

[TwelveSquared]

Alright, let's try this:
draw/CAD/etc. a Wheatstone bridge. Then state the equation used to find the resistance of an unknown resistor using it.