Why Is There a Negative Sign When Calculating Power with P=IV?

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When calculating power using the formula P=IV, a negative sign appears when the current is flowing in the opposite direction to the voltage, indicating that the source is absorbing power rather than supplying it. In the given example with a voltage of 24V and a current of 4A, if the current is defined as negative, the calculation results in negative power, signifying power absorption. This convention is essential for understanding the behavior of electrical components in a circuit. Clarifying the direction of current flow relative to voltage is crucial for accurate power calculations. Understanding these signs helps in analyzing circuit functionality effectively.
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i want to calculate the power supplied or absorbed by a source whose voltageis 24V and current is of 4A in the circuit. i used formula
P=IV ... but their is a negative sign with current ... please tell me why is it so ? Thanks
 
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taalha said:
i want to calculate the power supplied or absorbed by a source whose voltageis 24V and current is of 4A in the circuit. i used formula
P=IV ... but their is a negative sign with current ... please tell y is it so ? Thanks


Why does 4 * 24 give you a negative sign?
 

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