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Question
Three resistors of 6.0 Ω, 2.0 Ω and 4.0 Ω are joined to an ammeter A and a cell of emf 6.0 V as shown in the following figure. Calculate :
- the effective resistance of the circuit.
- the reading of ammeter.
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Solution
From circuit diagram
R3 and R2 are in series
R3 = i.e 4 + 2 = 6 Ω
Now R3 and R1 are in parallel
- Total resistance = `1/"R" = 1/6 + 1/6`
= `2/6` or
R = `6/2 `
= 3 Ω - I = `"V"/"R"`
= `6.0/3.0`
= 2 A
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