Basic Physics II Evidences - DrJJ - UiTM

Material SciencePHY407ii)Using a multimeter, record the potential difference (voltage) across thebattery terminals followed by the voltage across the bulb’s contact points.Points V PhET , volts V lab , voltsV battV bulbiii) Connect an ammeter tomeasure the current that flowsthrough the circuit. Record yourreading. Note that an ammeterMUST be connected in serieswith the bulb (You must breakthe circuit connection in order foryou to insert the ammeter).BAmAiv) Add another bulb in the circuit,observe the brightness of thebulbs and repeat steps (ii) and(iii).v) Add yet another bulb in thecircuit, observe the brightness ofthe bulbs and repeat steps (ii)and (iii).BBattery 6 VS 1AV bulb-1V bulb-2V bulb-3PhETVBrightness ABBulbs in SeriesV V V VBulb 1 none noneBulb 1 + Bulb 2noneBulb 1 + Bulb 2 +Bulb 3LABVBrightness AB V bulb-1 V bulb-2 V bulb-3Bulbs in SeriesV V V VBulb 1 none noneBulb 1 + Bulb 2noneBulb 1 + Bulb 2 +Bulb 3AI ABAI ABAPowerWattsPowerWattsv) Unscrew any bulb and observe what happens to the bulbs and to the currentin the circuit. Record your observation.Questions1. What causes the bulb to light up when the switch is thrown down?2. Why did the bulb go off when it is unscrewed from the holder?3. Did it matter if the polarity of the bulb is reversed? Why or why not?4. Why is the voltage the same when measured across the battery or across thebulb for a single circuit?5. What is the physical meaning of the current reading on the ammeter?6. What happens to the brightness of the first bulb, the voltage across it and thecurrent in the circuit when a second bulb is added in series to the circuit?Created by Dr. JJ, FSG, UiTM Shah Alam Page 4 of 7 3/3/2010