Equipment: DC powe supply, circuit board (fuse, switch, two bulbs), multimeter, wires.
From the data, I found the voltage drop of each components in the parallel circuit are the same, but in series circuit, voltage drop are different in all parts of the circuit.
Measured the current flow through the light bulb one, two and both circuits.
From the data, I found the current flow of the main circuit equals the total current flow through each components in parallel circuit.
Calculated the resistance of each bulb using V(supply voltage) / I(current through bulb one/two), then calculated the total resistance in this circuit using 1 / RT = 1 / R(bulb one) + 1 / R(bulb two).
Calculated the total watts used in this circuit using V(supply voltage) x I(total current), and watts used by each bulb using V(supply voltage) x I(current through bulb one or two).
These bulbs have more watts compare to the series circuit, because in the parallel circuit, voltage is the same for each components, so the current through each components is larger than series circuit, watts = V x I , so the bulb has more watts and looks brighter.
THREE BULBS
Equipment: DC powe supply, circuit board (fuse, switch, three bulbs), multimeter, wires.
I found the total amps has increased when the third bulb has added, but the current flow through other bulbs have not been changed, because the voltage and the resistance of other bulbs are still the same.
So I found the total amps in a parallel circuit, is the sum of the current flow through each components in this circuit.
Measured the available volts and the voltage drop across each of the lights.
When the third bulb was added into the circuit, the available voltage still the same, because in the parallel circuit the available voltage for each components are the same, no matter how many components in the circuit. The voltage drop in the circuit when the third bulb was added still the same, because inparallel circuit, each component uses al the voltage available to them which is the voltage available for the whole circuit.
Calculated the resistance of each bulb using V(available voltage) / I(current of bulb one, two and three), then calculate the total resistance of the circuit using 1 / RT = 1 / R1 + 1 / R2 + 1/R3, and the total watts used using V(available voltage) x I(total current in circuit).
