Question
State the sign convention for applying Kirchhoff's loop rules.
✓
Answer
→(1) If our journey through the resistor is in the direction of flow of current, IR ( $= V$ potential) should be considered negative and if the direction of journey and the direction of current are opposite to each other, IR should be considerd positive (while writing on the left side of the equation.)
(2) The emf of a battery should be considered positive while moving from negative terminal to the positive terminal of a battery (while writing on the left side of the equation.) The emf of a battery should be considered negative while moving from positive to the negative terminal of a battery.
→The direction of the electric current can be arbitrarily chosen while using Kirchhoff's rules to analyze any network. If we shall get negative value of the current, the direction of current which is arbitrarily chosen is opposite to the actual direction of current.
(2) The emf of a battery should be considered positive while moving from negative terminal to the positive terminal of a battery (while writing on the left side of the equation.) The emf of a battery should be considered negative while moving from positive to the negative terminal of a battery.
→The direction of the electric current can be arbitrarily chosen while using Kirchhoff's rules to analyze any network. If we shall get negative value of the current, the direction of current which is arbitrarily chosen is opposite to the actual direction of current.
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