Which of the following terms does not represent electrical power in a circuit?
(a) I2R (b) IR2 (c) VI (d) V2/R
(b) Electrical power is given by the expression, P = VI … (i)
According to Ohm’s law, V = IR … (ii)
Where,
V = Potential difference
I = Current
R = Resistance
P = VI
From equation (i), it can be written
P = (IR) × I
P = I2R
From equation (ii), it can be written
Power P cannot be expressed as IR2.
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