Question -
Answer -
(a) 100 W (b) 75 W
(c) 50 W (d) 25 W
Answer
25 W
Explanation:
The energy consumed by the appliance is given by the expression
P = VI = V2/R
The resistance of the light bulb can be calculated as follows:
R = V2/P
Substituting the values, we get
R = (220)2/100 = 484 Ω
Even if the supply voltage is reduced, the resistance remains the same. Hence, the power consumed can be calculated as follows:
P = V2/R
Substituting the value, we get
P = (110)2 V/484 Ω = 25 W
Therefore, the power consumed when the electric bulb operates at 110 V is 25 W.