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fawk3s
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Homework Statement
http://desmond.imageshack.us/Himg705/scaled.php?server=705&filename=fafadaf.png&res=landing [Broken]
Find resistances R2 and R3 in such a way that the power on the resistances (shown by the watt-meter) remains constant when the switch SA1 is opened.
Homework Equations
I=V/R
1/R=1/R2+1/R3
Rwhole=R+Rs
P=I*V
The Attempt at a Solution
I've tried many things already but none have got me anywhere really. I understand that P=I*V which means that when "V" decreases n times, then "I" must increase by n times, but I don't really know what do with it. When the switch is opened, V on R2 ought to be bigger than when it is closed and I ought to be smaller than when the switch is closed.
But that's all I've got. :/
PS. Dont mind the R3=2,45 in the picture. Both R2=R3=?
Thanks in advance,
fawk3s
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