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Question
An electric motor takes 5 A from a 220 V line. Determine the power of the motor and the energy consumed in 2 h.
Solution
Power (P) is given by the expression P = VI
Where,
Voltage,V = 220 V
Current, I = 5 A
P = 220 × 5
P = 1100 W
Energy consumed by the motor = Pt
Where,
Time, t = 2 h
= 2 × 60 × 60
= 7200 s
∴ P = 1100 × 7200
= 7.92 × 106 J
Therefore, power of the motor = 1100 W
Energy consumed by the motor = 7.92 × 106 J
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