Help needed on Intro to EE, Howework Problem

[memphisBred]

10V/I - R1- R2 = R3

20V/I - R1 - R2 - R3 = R4

[Wicks]

You're gettin' it.

Now back to the second issue.

Your 4th resistor only provides 20V and you're connecting it to the source........?

[memphisBred]

Thanks for the help!

So far I've gotten R1= 1000, R2 = 4000, R3 = 5000, R4 = 10000, which is 20,000 ohms /.001A = 20 V....like you said. How exactly do you get to 25 V?

[memphisBred]

Another 5000 ohm resistor?

[Wicks]

The answer is easy, you're just thinking too hard about it.

Your source is at 25V and the top of your resistor string is at 20V.

So you need to drop the source by another 5V in order to connect the two.

What in the circuit would help you drop 5V?

[Wicks]

Ninja'd me.

Yup you got it.

They try to trick you by stating you need to get 4 lower voltages so you assume that you need 4 resistors when in fact, you need 5.

[memphisBred]

Thanks ALOT! I have another question if you have time? I'll pm it.

[Ray]

Surprised you're doing this before kirchhoff's voltage law

R1xr2xr3xr4

---------------- =

R1+r2+r3+r4

This is very practical even in car audio.

I use it in every ford i do that has factory amps.

I should prob enroll in a class.

Good to see you getting this.

[memphisBred]

The teacher is real smart, but he is kind of wanting us to teach ourselves this stuff/first assignment to gauge what we know/how we learn. Definitely interesting/fun learn about this stuff.

It's nice when stuff clicks. Out of the 20 problems this was the only real hick up.

[Wicks]

^^^Agree with Ray

Everybody into car audio should take EE101.

Very useful to understand alternators/batteries, wiring, loads, dividers, how current works, etc...

Also knowing the Voltage and Current Laws is a real help.