A learner asked the following question: What happens to the current in a circuit if the resistors are connected in parallel? she then proceeds to the investigate her question using four identical resistors. a) write down an appropriate hypothesis for her investigation. b)write down the dependent and independent in her investigation. c)give a list of apparatus (Excluding resistors) she will need to conduct her investigation. d)Describe in point form how she go about doing her investigation and what readings she should take at each step.
First measure resistance with each of them with (1)voltmeter and (2) ammeter and your battery.
R = V/i
They better be the same.
now hook in series.
current better be V/ 4R (this is just a check for completeness)
THEN
when I hook them in parallel I hypothesize that I will get i = V/R through each. Check that with voltmeter and ammeter
Then my total current I = V/R + V/R + V/R + V/R if the original i = V/R goes through each
so
I = 4 V/R = V/ (R/4)
so my equivalent R should be Requiv = R/4
a) An appropriate hypothesis for her investigation could be: "If resistors are connected in parallel in a circuit, the current flowing through the circuit will increase compared to when the resistors are connected in series."
b) The dependent variable in her investigation would be the current in the circuit, while the independent variable would be the type of resistor connection (parallel or series).
c) The learner will need the following apparatus (excluding the resistors) to conduct her investigation:
- Power supply or battery
- Ammeter (to measure current)
- Connecting wires
- Switch (optional)
d) Here is a step-by-step description of how she can conduct her investigation and what readings she should take at each step:
1. Set up the circuit with four identical resistors. Connect the resistors in parallel.
2. Connect the power supply or battery to the circuit.
3. Use the ammeter to measure the current flowing through the circuit.
4. Record the current reading.
5. Disconnect the power supply or battery from the circuit.
6. Reconfigure the circuit by connecting the four resistors in series.
7. Reconnect the power supply or battery to the circuit.
8. Use the ammeter to measure the current flowing through the circuit.
9. Record the current reading.
10. Compare the current readings obtained in steps 4 and 9.
11. Analyze the results and draw a conclusion regarding the effect of resistor arrangement (parallel or series) on the current in the circuit.
12. Repeat the experiment multiple times to ensure the reliability of the results.
By following these steps and taking readings at each stage, the learner can investigate and determine the impact of connecting resistors in parallel on the current in the circuit.