Physics
In figure, calculate —
(a) the total resistance of the circuit,
(b) the value of R, and
(c) the current flowing in R
Current Electricity
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Answer
(a) Given,
V = 4 V
I = 0.4 A
From Ohm's law
V = IR
4 = 0.4 x R
⇒ R = 4 / 0.4 = 10 Ω
Hence, total resistance of the circuit = 10 Ω
(b) As total resistance of the circuit is equal to 10 Ω and the two resistors R and 20 Ω are connected in parallel, hence we get,
Hence, the value of R = 20 Ω
(c) current flowing in R = ?
V = 4 V
R = 20 Ω
I = ?
From Ohm's law
V = IR
⇒ 4 = I x 20
⇒ I = 4 / 20 = 1 / 5 = 0.2 A
Hence, the current flowing in R = 0.2 A
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