A battery of em.f 12v and internal resistance r =1.5ohms is connected to an external resistance of 30ohm calculate the potential drop across the 30ohm resistance and in the internal resistance
The circuit can be represented as follows:
___________ ____________ ________
| |----| 30 ohm |----| |
| 12V | | resistor | | 1.5ohm|
| battery |----| |----| |
|_________| |___________| |______|
Using Ohm's law, we can calculate the current flowing through the circuit:
I = V / R
where V is the voltage of the battery, and R is the total resistance of the circuit:
R = 30 ohm + 1.5 ohm = 31.5 ohm
I = 12V / 31.5 ohm = 0.38 A
Now we can calculate the potential drop across the 30 ohm resistor:
V = I * R
V = 0.38 A * 30 ohm = 11.4 V
Finally, we can calculate the potential drop across the internal resistance of the battery:
V = I * r
V = 0.38 A * 1.5 ohm = 0.57 V
Therefore, the potential drop across the 30 ohm resistor is 11.4 V, and the potential drop across the internal resistance is 0.57 V.
To calculate the potential drop across the 30-ohm resistance and in the internal resistance of the battery, we can use Ohm's Law and the concept of voltage division.
1. Calculate the current flowing through the circuit:
The total resistance in the circuit (including the external resistance and the internal resistance) can be found by adding the two resistances together:
Total Resistance (Rt) = External Resistance (Re) + Internal Resistance (Ri)
Rt = 30 ohms + 1.5 ohms = 31.5 ohms
Now we can use Ohm's Law to calculate the current (I) flowing through the circuit:
I = V / R
Where V is the battery emf (electromotive force) and R is the total resistance.
I = 12V / 31.5 ohms
2. Calculate the potential drop across the 30-ohm resistance:
The potential drop (Vd) across a specific resistor can be calculated using Ohm's Law:
Vd = I * Re
Vd = I * 30 ohms
3. Calculate the potential drop across the internal resistance:
The potential drop (Vi) across the internal resistance can also be calculated using Ohm's Law:
Vi = I * Ri
Vi = I * 1.5 ohms
Substituting the value of I calculated in step 1 into steps 2 and 3 will give us the potential drops across the 30-ohm resistance and in the internal resistance.