Calculating Effective resistance

  • Thread starter pratyushag
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  • #1
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Homework Statement



In the given circuit,the equivalent resistance between points A and B will be?

Homework Equations





The Attempt at a Solution


My solution

Effective resistance will be 2Ω+2Ω=4Ω as the current will not enter the triangle as equal amt of current enter from opposite sides(Im not sure about this part)
 

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Answers and Replies

  • #2
SammyS
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Homework Statement



In the given circuit,the equivalent resistance between points A and B will be?

Homework Equations



The Attempt at a Solution


My solution

Effective resistance will be 2Ω+2Ω=4Ω as the current will not enter the triangle as equal amt of current enter from opposite sides(Im not sure about this part)
Correct !
 
  • #3
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But why doesnot current enter if opp sides have equal amt of current
 
  • #4
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But why doesnot current enter if opp sides have equal amt of current

Not sure what do you mean by "opp sides". If you redraw the circuit (see attachment), the three resistors short and no current flows through them.
 

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  • #5
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Why do the resistors short?
 
  • #6
SammyS
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There is no potential difference across those 3 resistors in the "loop".
 
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  • #7
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But why doesnot current enter if opp sides have equal amt of current

there is current in the loop that arrive at the same node, but the current is negligible. meaning not worth mentioning.

if you take one part of the loop at the same node to connect after the resistor near B, thereby creating another node, current that enters that series of 3 x 2Ω will meet at another node, this created a potential difference, and usually with p.d. and resistance, you can work out the I.
 
  • #8
CWatters
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Why do the resistors short?

because there is a physical short circuit shown in your original circuit.

The drawing produced by Pranav-Arora is electrically the same as yours just a different physical shape. He's not added any wire or nodes just changed the physical shape of the existing node.
 

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