A battery of emf and internal resistance is connected to an external resistor of

PHYSICS · Multi-part · CBSE · Physics · Current Electricity · Current Electricity

Problem

A battery of emf

12\,\text{V}

and internal resistance

2.0\,\Omega

is connected to an external resistor of

10\,\Omega

. After some use, the emf falls to

11\,\text{V}

while the internal resistance remains unchanged. (i) Find the initial current in the circuit. (ii) Calculate the power dissipated in the external resistor initially. (iii) Determine the current after the emf has fallen to

11\,\text{V}

. (iv) Find the heat produced in the external resistor in

2.0\,\text{min}

after the emf drop.

Related theory

Electric Power
Compound Circuits
EMF, internal resistance and terminal voltage
Electric Circuits
Electricity
EMF and internal resistance
Current Electricity
Cells emf and internal resistance

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