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Question
Two resistors of 4Ω and 6 Ω are connected in parallel to a cell to draw 0.5 A current from the cell.
(i) Draw a labelled circuit diagram showing the above arrangement.
(ii) Calculate the current in each resistor. What is an Ohmic resistor?
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Solution
i.
The parallel combination of two resistors 4 Ω and 6 Ω that draws a current of 0.5 A from the cell is as shown below.
ii.
In parallel combination of resistors potential difference across each resistor is same as the potential difference across the terminals of the battery.
Here current drawn from cell, I = 0.5 A
The effective resistance `1/R=1/R_1+1/R_2`
Here R1=4Ω and R2=6Ω
`therefore 1/R=1/4+1/6`
`therefore 1/R=5/12`
`therefore R=12/5`
`therefore R=2.4 Omega`
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