Slashz
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Slashz said:Homework Statement
R1-10
R2-13
r3-3
R4-6
What should be the total voltage so that I3 = 1A.
Homework Equations
n/a
The Attempt at a Solution
idk to solve it help me plss :(
Have you not learned about Kirchhoff's laws? KVL? KCL?Slashz said:ohh sorry so this is my attempt.
1. You haven't identified where I3 is (Is it the current through R3?).Yes
2. There must be relevant equations! Otherwise, how would such problems get solved?
http://en.wikipedia.org/wiki/Ohm's_law
Note that R1 is in parallel with the voltage source (let's call it V) . If the voltage source is ideal then the potential with respect to ground at the node where R1 and R2 meet is fixed by V regardless of the value of R1. So we can expect that the value of R1 will not play a role in determining V.3. You need to provide some attempt at a solution, or at least some discussion of what you've already tried.
Rt=R1+R2+R34
Rt=10+13+2
Rt=25
Since you've determined the voltage that appears across R3 above, what can you say about the current through R4?I3=1
V3=I3R3
V3=1(6)
V3=6 <--- Okay, good!
I4=I2-I3
I4=I2-1
I2-I4=1 <--- Okay! (Note that you've used KCL)![]()