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Question
Two resistors of resistance 4 Ω and 6 Ω are connected in parallel to a cell to draw 0.5 A current from the cell.
Calculate current in each resistor.
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Solution
Equivalent resistance of the circuit:
`1/"R" = 1/4 + 1/6 = (3+2)/12 = 5/12`
`therefore "R" = 12/5 = 2.4 Omega`
Hence, the emf of the cell is
V = IR
∴ V = 0.5 × 2.4
∴ V = 1.2 V
Therefore, current through each resistor is
`"I"_4 = "V"/"R"_4 = 1.2/4 = 0.3 "A"`
`"I"_6 = "V"/"R"_6 = 1.2/6 = 0.2 "A"`
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