If the emf of a battery is 23 V and a current of
66 A is measured when the battery is shorted,
what is the internal resistance of the battery?
Answer in units of Ω
How would you set up the equation to solve?
Voltage = Current x Resistance
or V = IR
To solve for the internal resistance of the battery, we can use Ohm's Law. Ohm's Law states that the current (I) flowing through a conductor is equal to the voltage (V) across the conductor divided by its resistance (R):
I = V / R
In this case, the current (I) is given as 66 A and the voltage (V) is given as 23 V. We can rearrange Ohm's Law to solve for the resistance (R):
R = V / I
To find the internal resistance, we need to use the measured current when the battery is shorted. When a battery is shorted, the internal resistance is effectively in parallel with the load resistance, resulting in a maximum current flow. So in this case, the measured current of 66 A is the maximum possible current.
Now we can substitute the values into the equation:
R = 23 V / 66 A
R = 0.348 Ω (rounded to three decimal places)
Therefore, the internal resistance of the battery is approximately 0.348 Ω.