Two batteries of emf's 6.20 V and 12.45 volt and internal resistance 0...
Terminal Potential Differences during Charging
Calculating Terminal Potential Difference
The terminal potential difference of a battery can be calculated using the formula:
Vt = emf - Ir
Where Vt is the terminal potential difference, emf is the electromotive force, I is the current, and r is the internal resistance.
Calculating Current
Since the battery charger supplies a current of 20 amperes, the current flowing through each battery will also be 20 amperes.
Calculating Terminal Potential Difference for 6.20 V Battery
Using the formula above, we can calculate the terminal potential difference for the 6.20 V battery:
Vt = 6.20 - (20 x 0.01)
Vt = 5.20 V
Therefore, the terminal potential difference for the 6.20 V battery during charging is 5.20 V.
Calculating Terminal Potential Difference for 12.45 V Battery
Using the same formula, we can calculate the terminal potential difference for the 12.45 V battery:
Vt = 12.45 - (20 x 0.03)
Vt = 11.85 V
Therefore, the terminal potential difference for the 12.45 V battery during charging is 11.85 V.
Explanation
During charging, the battery charger supplies a current which flows through the batteries. As the current flows through the batteries, it encounters resistance due to the internal resistance of the batteries. This resistance causes a voltage drop, which reduces the terminal potential difference of the batteries.
The formula for calculating the terminal potential difference takes into account both the electromotive force of the battery and the voltage drop due to the internal resistance. By subtracting the product of the current and the internal resistance from the electromotive force, we can determine the terminal potential difference of the battery during charging.
In this case, the terminal potential difference for both batteries is reduced due to the current flowing through them and the resistance of their internal components. However, the larger battery with a higher emf and internal resistance has a higher terminal potential difference after accounting for the voltage drop.