(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

http://jbworld.jbs.st-louis.mo.us/science/mschober/em3-circuits/E3ws4.pdf

It's the very first one.

2. Relevant equations

R_eq = delta V / I = [ 1/R_1 + 1/R_n] ^ -1

I = V / R

3. The attempt at a solution

a) So, since the resistors are in parallel, the potential different across the three different resistors have to be same.

The given, I have 6V.

Therefore, delta V from a to b should be 0 V to 6 V.

b) Current between a and b :

I_a to b= V / R_ab = 6 V / 12 ohm = 1/2 A

I_c to d= 6V / 6 ohm = 1 A

c) Since it is just a wire, current point at g should be 6 V / 0 ohm = 0 A

d ) before the switch is closed, I do not have a current flow, so .. resistance is zero.

After the switch is closed,

R_eq = [1/12 + 1/6 + 1/30]^-1 = 3.529 ohm

Does everything sounds good to anyone? :( man. I suck at circuit.

---------

shoot,

um.. can somebody help me with the number 6 also?

I solved a:

R_a to b & c to d = [1/12 + 1/6]^-1 = 4ohm

then R_eq = 4ohm + 8 ohm = 12 ohm

But how can I find the each resistor's current passing and delta V ( b and c )??

Since the Power = I x delta V , I guess I can help myself if I find b and c.

HELP~~~~ please ~~~

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# Homework Help: Closing a circuit

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