PHYSICS â€“ An investigation to find out how altering the current in a bulb affects the resistance of a filament bulb.
Equipment you will need: 12V filament bulb, Connecting wires, Variable power supply, Ammeter and Voltmeter Practical Method: Set the equipment up as shown in the diagram below; Variable Power Supply
Switch on the variable power supply and take the readings from the ammeter and voltmeter. Record them. Calculate the resistance of the bulb (R=V/I). Change the setting on the power supply and repeat the steps above. Repeat for 5 different readings on the power supply.