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Resistors

Samuel2100

Sep 14, 2016
1
Joined
Sep 14, 2016
Messages
1
hey,

What is the total power loss if 2 k
omega.gif
and 1 k
omega.gif
parallel-connected resistors have an IT of 3 mA?

A. 6
mu.gif
W
B. 36
mu.gif
W
C. 6 mW
D. 36 mW

cheers,

sam
 
Last edited:

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Jan 21, 2010
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What formulae do you have for calculating power?

Do you have one involving current and resistance?
 

Harald Kapp

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Nov 17, 2011
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You have several ways to calculate this, once you have the equations at hand as asked by Steve.
  • calculate the equivalent total resistance and from that the total power using the known current IT
  • calculate the distribution of the total current IT among the parallel resistors, from that calculate power dissipation within each resistor, then add up partial results
 

Colin Mitchell

Aug 31, 2014
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As you get more advanced, you will know that the current will flow in the two resistors such that twice the current will flow in the 1k resistor.
But it is much easier to have a big block of chocolate and cut it into 3 pieces. I get twice as much as you.
This means you can work out in your head, the current through each resistor.
Now use the formula that states power is . . . . . . . . . . for the 1k and power is: . . . . . for the 2k.
Then add the two values together.
 
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