A battery of internal resistance 1 Ω and emf of 12 volt connected to external resistance of 79 Ω.Calculate the power delivered b
1 answer:
Answer:
<em>P = 1.8 Watt</em>
Explanation:
<u>Electromotive Force (EMF)</u>
It consists of a DC source ε with small internal resistance Ri. When it's connected to an external resistance Re a current i flows by the circuit whose value is given by:
The internal resistance of the battery is Ri=1 ohm and its emf is ε=12 V. When connected to an external resistance of Re=79 ohm, the current is:
i = 0.15 A
The power delivered by the battery is:
P = ε.i
P = 12 V * 0.15 A
P = 1.8 Watt
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