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Question
The figure given below shows an electric circuit in which current flows from a 6 V battery through two resistors.
- Are the resistors connected in series with each other or in parallel?
- For each resistors, state the p.d. across it.
- The current flowing from the battery is shared between the two resistors. Which resistor will have bigger share of the current?
- Calculate the effective resistance of the two resistors.
- Calculate the current that flows from the battery.
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Solution
- The resistors are connected in parallel.
- In a parallel arrangement, the voltage remains the same across each resistor. The battery is also connected in parallel with the resistors. Therefore, the p.d across each resistor is 6 V.
- The 2 Ω resistor will have the bigger share of the current since resistance is inversely proportional to the current.
- The effective resistance of the parallel combination is: `1R=1R_1+1R_2 1R=12+13 1R= 3 + 261 R = 56R = 65Ω R = 1.2 Ω `
`1/R=1/R_1+1/R_2`
`1/R=1/2+1/3`
`1/R=3+2/6`
`1/R=5/6`
`R=6/5` Ω
`R=1.2` Ω - The current flowing through the battery, I = 5 A
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