A battery has a terminal voltage of 12.0 V when no current flows. Its internal resistance is 2.0 Ω. If a 7.2 Ω resistor is conne
1 answer:
Answer:
Voltage= 9.4 V
Current= 1.3 A
Explanation:
Equivalent resistance will be the sum of two resistors hence
=2+7.2=9.2Ω
From Ohm's law, V=IR where I is current, R is equivalent resistance and V is voltage
Terminal voltage will be given by V=e-Ir where r is internal resistance, I is current and e is electromotive force.
From Ohm's law, current is given by dividing emf of the battery by the equivalent resistance hence
This is the current through external resistor
Terminal voltage will be given by V=e-Ir hence V=12-(1.3*2)=9.4 V
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