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प्रश्न
(a) Calculate the total resistance across AB.
(b) If a cell of e.m.f 2.4 V with negligible internal resistance is connected across AB then calculate the current drawn from the cell.
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उत्तर
(a) Resistors 3 Ω and 5 Ω are in series. The equivalent resistance of these two is 8 Ω.
Now, this 8 Ω is connected with another 8 Ω resistors in parallel.
The equivalent resistance of these two is
`= (8 xx 8)/(8 + 8)`
`= 64/16`
= 4 Ω.
Thus, the total resistance across AB is 4 Ω.
(b) If a cell of e.m.f 2.4 V with negligible internal resistance is connected across AB then the current drawn from the cell is
`= ("Voltage" ("V"))/("equivalent resistance" ("R"))`
`= 2.4/4`
= 0.6 A.
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संबंधित प्रश्न
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- the current drawn from the cell.
- the p.d. across the cell.
- voltage drop inside the cell.
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A battery of e.m.f 3.0 V supplies current through a circuit in which the resistance can be changed.
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Define the e.m.f. (E) of a cell and the potential difference (V) of a resistor R in terms of the work done in moving a unit charge. State the relation between these two works and the work done in moving a unit charge through a cell connected across the resistor. Take the internal resistance of the cell as ‘r’. Hence obtain an expression for the current i in the circuit.
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(iii) The current through each resistance.
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