Relationshipbetweenvir
- 1. RELATIONSHIP BETWEEN V, I&R YEAR 9 – ELECTRICITY
- 2. AIM & HYPOTHESIS Aim: To find out how voltage, current and resistance in an electric circuit are related. Hypothesis: (Write your hypothesis here)
- 3. EQUIPMENT • power pack • two resistors of known (but different)resistance value • voltmeter • ammeter • switch • 6 connecting wires • alligator clips
- 4. RISK ASSESSMENT Risk Injury Prevention Fill out a risk assessment for your experiment
- 5. METHOD 1. Set up an electric circuit as shown for one resistor. 2. Set the power pack to 2 volts DC. Close the switch and read the voltmeter and ammeter.
- 6. METHOD 3. Record the voltage V and current I in your results. 4. Repeat the measurements for a number of different power pack settings 4V, 6V and 8V. 5. Record all results. 6. Repeat steps 2 to 5 using the other resistor. 7. Calculate the average resistance for each resistor.
- 7. METHOD 8. Construct a graph of voltage versus current for each resistor on the same set of axes. 9. Calculate the slope of the graph for each resistor. The slope of the graph is the resistance value. Compare this to the known values of the resistors.
- 8. RESULTS (Heading for your table) Resistor 1 Voltage (V) 2 4 6 8 Current (A) Voltage ÷ Current (Resistance, Ω) Resistor 2 Current (A) Voltage ÷ Current (Resistance, Ω)
- 9. DISCUSSION 1. Compare the average resistance calculated with the actual resistance from the slope of the graph. 2. Suggest reasons for any differences. 3. Describe the shape of the graphs and use it to predict what would occur if: a. the voltage was doubled b. the resistance was doubled
- 10. CONCLUSION • Write a conclusion for your experiment here.