Calculate Unknown Emf Value | Power Dissipation

Thread starter phykon
Start date Jul 2, 2010
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Power

AI Thread Summary

To calculate the unknown emf value in the given circuit, users should sum the power dissipations from point A to point B. For resistors, the power dissipation is calculated using the formula I^2*R, while for voltage sources, the formula is I*V. It's important to consider the sign of the voltage source, where a drop in the direction of current (I) is positive and a gain is negative. Proper application of these principles will lead to the correct determination of the unknown emf. Accurate calculations are crucial for understanding circuit behavior.

Jul 2, 2010

phykon

What is the value of unknown emf in this pic please help me?[PLAIN]http://www.atiani.com/int.gif

Last edited by a moderator: May 4, 2017

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Jul 3, 2010

dighn

just sum up the power dissipations from a to b, for resistors use I^2*R, for voltage sources use I*V and pay attention to the sign of of the source (a drop in the direction of I is +V, gain -V).

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