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Question
Which of the following terms does not represent electrical power in a circuit?
Options
I2R
IR2
VI
`"V"^2/"R"`
Solution
IR2
Explanation:
Electrical power is given by the expression P = VI ....(i)
According to Ohm’s law,
V = IR
Substituting the value of V in (i), we get
P = (IR) × I
P = I2R
Similar, to Ohm’s law,
I = `"V"/"R"`
Substituting the value of I in (i), we get
P = `"V" xx "V"/"R" = "V"^2/"R"`
From this, it is clear that the equation IR2 does not represent electrical power in a circuit.
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