Question: Which of the following terms does not represent electrical power in a circuit? A. \[{I^2}R\] B....

Question

Which of the following terms does not represent electrical power in a circuit?
A. ${I^2}R$
B. $I{R^2}$
C. VI
D. $\dfrac{{{V^2}}}{R}$

Answer 1

Solution

Electric power is the rate at which electrical energy is transmitted by an electric circuit per unit of time. The watt, or one joule per second, is the SI unit of power.Electric generators are the most common source of electricity, however other sources such as electric batteries can also be used.

Complete step by step answer:
Electric power, like mechanical power, is the rate at which work is completed, measured in watts and symbolised by the letter P. Wattage is a slang word that means "electric power in watts." An electric current I carrying a charge of Q coulombs per t seconds flowing through an electric potential (voltage) differential of V produces an electric power in watts.
$P = {\text{work done per unit time}} = \dfrac{W}{t} = \dfrac{W}{Q}\dfrac{Q}{t} = VI{\mkern 1mu}$ --(1)

According to Ohm's law, the current flowing through a conductor between two locations is proportional to the voltage across the conductor. When the proportionality constant, resistance, is included, the typical mathematical equation that represents this connection emerges:
$I = \dfrac{V}{R}$ ---(2)
When we substitute equation (2) for (1), we obtain
$P = (IR)I$
$\Rightarrow P = {I^2}R$ ............................ (3)
According to Ohm's rule,
I = $\dfrac{V}{R}$ ...................... (4)
Substituting equation (4) into equation (1) yields
P = $\dfrac{{{V^2}}}{R}$ ........................ (5)
The electric power is represented by the equations (1), (3), and (5), However the electric power is not represented by $I{R^2}$ .

Note: Make sure you follow the correct unit conversions. There is no other method to solve the problem. Electric power is widely employed in industrial, commercial, and consumer applications because it is generated at central generating stations and delivered through an electrical transmission grid. A country's per capita electric power consumption is linked to its industrial growth. Electric motors are used to propel subways and railway trains, as well as to power manufacturing machines.