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
Answered by Shivani Kumari | 2 years agoExplain the following.
a. Why is the tungsten used almost exclusively for filament of electric lamps?
b. Why are the conductors of electric heating devices, such as bread-toasters and electric irons, made of an alloy rather than a pure metal?
c. Why is the series arrangement not used for domestic circuits?
d. How does the resistance of a wire vary with its area of cross-section?
e. Why copper and aluminum wires are usually employed for electricity transmission?
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