I am stuck on three questions from a lab report. I know the equation for the first question but not sure which values to use for I to find the internal resistance of the battery. The second question I am not sure what to use in this circuit to find electrical power. The last question I have no idea.
1. Evaluate the internal resistances of the batteries using the obtained data.
(I figured out the equation for the first battery would be ε= V-Ir and then the same for the second battery in the circuit. But I am not sure of which current to use based on all my measurements.)
2. Calculate the electric power developed in the circuit you measured. (No idea what to use for this circuit since P = W/t)
3. Could you calculate the electric power developed in the circuit, if the resistances of the resistors are unknown Explain.
Actual: R1=102 Ω, R2=198 Ω, R3=295 Ω and R4 =506 Ω. We didn't measure the atual for the two EMF sources so I guess I would need to use the given values.
Measured Data for the circuit.
| Junction B (IBF + IBAGF + IBCDF = 0) |
Junction F (-IGF + -IBAGF + -IBCDF = 0) |
| IBAGF (mA) |
7.50 |
IBAGF (mA) |
-7.46 |
| IBF (mA) |
6.42 |
IGF (mA) |
-6.39 |
| IBCDF (mA) |
-13.84 |
IBCDF (mA) |
13.88 |
| Experimental Net Current (mA) |
0.08 |
Experimental Net Current (mA) |
0.03 |
| Junction B and F Positive Currents |
Junction B and F Negative Currents |
| IBAGF (mA) |
7.50 |
IBAGF (mA) |
-7.46 |
| IBF (mA) |
6.42 |
IGF (mA) |
-6.39 |
| IBCDF (mA) |
13.88 |
IBCDF (mA) |
-13.84 |
| Net Positive Currents |
27.80 |
Net Negative Currents |
-27.69 |
| Percent Difference (Pos/Neg) |
0.40% |
|
|
| For the loop ABFGA: |
For the loop BCDFB: |
For the loop ABCDFGA: |
| R3 IBAGF |
2.198 |
R1 IBCDF |
1.417 |
R3 IBAGF |
2.199 |
| R2 IBF |
-1.267 |
R2 IBF |
1.266 |
R1 IBCDF |
1.418 |
| R4 IBAGF |
3.777 |
?2 |
-2.685 |
R4 IBAGF |
3.778 |
| ?1 |
-4.709 |
Net Voltage |
-0.002 |
?1 |
-4.712 |
| Net Voltage |
-0.001 |
Percent Difference (Bat/RES) |
0.07% |
?2 |
-2.687 |
| Percent Difference (Bat/RES) |
0.02% |
|
|
Net Voltage |
-0.004 |
|
|
|
|
Percent Difference (Bat/RES) |
0.05% |