Lab #14: Current Electricity Mini-Labs
Dates: 2/12, 2/14, 2/19, 2/21
Circuit Mini-Lab A:
The voltage across the cell was 1.3V
The voltage across the bulb was 0.97V
-The voltages across the bulb and across the cell are approximately equal in magnitude.
The voltage across the bulb was 0.97V
-The voltages across the bulb and across the cell are approximately equal in magnitude.
Circuit Mini-Lab B:
The light bulb produces more light and is brighter.
The light bulb does not produce light when we open the switch, and when closing the switch it does.
Voltage across the battery is 1.944
Voltage across the bulb is 1.726
The voltages across the bulb and across the cells are approximately equal in magnitude.Both batteries lost some voltage.
The light bulb does not produce light when we open the switch, and when closing the switch it does.
Voltage across the battery is 1.944
Voltage across the bulb is 1.726
The voltages across the bulb and across the cells are approximately equal in magnitude.Both batteries lost some voltage.
Mini-Lab C
When you one of the bulbs, the other one does not light.
The voltage across the battery is 2.1V and the voltage across the bulb is 1.855
The voltages of the two bulbs add up to the voltage across the battery.
The voltage across the battery is 2.1V and the voltage across the bulb is 1.855
The voltages of the two bulbs add up to the voltage across the battery.
Mini-Lab D
When you unscrew one bulb, the other bulb gets brighter.
The voltage across the battery is 1.559v and the voltage across the bulb is 1.162
The battery voltage equals the voltage drop between the bulbs in parallel.
The voltage across the battery is 1.559v and the voltage across the bulb is 1.162
The battery voltage equals the voltage drop between the bulbs in parallel.
Mini-Lab E
part b.
The resistance of three bulbs is 3.1. It adds the resistance of the individual light bulbs.
Part C.
The resistance of all three bulbs together in the parallel arrangement is 0.5, which is the half of the resistance of three light bulbs in a series.
Mini-Lab F
Mini-Lab G
The equivalent resistance of a 100 ohm, a 330 ohm, and a 82 ohm resistor in a series is 512 ohm, which is the sum of the resistances.
The measured value of the three resistors was 547, which is close to the calculated value.
The measured value of the three resistors was 547, which is close to the calculated value.
Mini-Lab H
The equivalent resistance of a 100 ohm, a 330 ohm, and a 82 ohm resistor in a parallel arrangement is 40 (1/(1/330+ 1/100 + 1/82))
The measured value of the three resistors in a parallel arrangement was 42.2, which is close to the calculated value.
The measured value of the three resistors in a parallel arrangement was 42.2, which is close to the calculated value.
Mini-Lab I
The calculated equivalent resistance is 219.67 ohm, and the measured equivalent resistance is 224.13 ohm, which is close to the calculated value.
Mini-Lab J
I=V/R
R=100 ohm + (1/(1/33+1/82))= 165.680 A => 6V/165.680= 0.036 => I1 : I1 is the same throughout the current because it is in a circuit.
2.3645/330 ohm= 0.007165 A =>I2
2.23645/82 ohm= 0.0288 A => I3
The sum of currents entering (0.036 A) the junction equals the sum of the currents leaving (0.007165+0.0288) the junction .
Voltage across I 1 is 0.0327 A, 0.026 A across I 3, and 0.006 A across I 2.
Based on Kirchoff's second rule, the net potential difference around one complete circuit is zero, which hold true in this circuit because: 0.036-(0.007165+0.0288)=0
R=100 ohm + (1/(1/33+1/82))= 165.680 A => 6V/165.680= 0.036 => I1 : I1 is the same throughout the current because it is in a circuit.
2.3645/330 ohm= 0.007165 A =>I2
2.23645/82 ohm= 0.0288 A => I3
The sum of currents entering (0.036 A) the junction equals the sum of the currents leaving (0.007165+0.0288) the junction .
Voltage across I 1 is 0.0327 A, 0.026 A across I 3, and 0.006 A across I 2.
Based on Kirchoff's second rule, the net potential difference around one complete circuit is zero, which hold true in this circuit because: 0.036-(0.007165+0.0288)=0
Reflection: These labs helped me understand circuits, currents, voltage, parallel and series arrangement, resistance, and Kirchoff's laws. I found these mini-labs very effective and helpful.