How many 176 Ω resistors (in parallel) are required to carry 5 A on a 220 V line?
For x number of resistors of resistance 176 Ω, the equivalent resistance of the resistors connected in parallel is given by Ohm’s law as
Where,
Supply voltage, V = 220 V
Current, I = 5 A
Equivalent resistance of the combination = R, given as
From Ohm’s law,
Therefore, four resistors of 176 Ω are required to draw the given amount of current.
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A hot plate of an electric oven connected to a 220 V line has two resistance coils A and B, each of 24 Ω resistance, which may be used separately, in series, or in parallel. What are the currents in the three cases?
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