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Question
Observe the given circuit diagram and answer the questions that follow:
- Calculate the resistance of the circuit when the key K completes the circuit.
- Calculate the current through 3Ω resistance when the circuit is complete.
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Solution
a. R1 = 5 + 3 = 8Ω
R2 = `(8 xx 2)/(8 + 2)`
R2 = 1.6Ω
∴ R = 1.6 + 0.4 = 2Ω
b. I = `E/R`
I = `4/2`
I = 2A
I3Ω = `(2 xx 2)/10`
I3Ω = 0.4A
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