Q1. You are told that the charge on a capacitor is Q. The actual charges on its plates are:
A. Q on each plate
B. Q on one plate and – Q on the other plate
C. Q/2 on one plate and – Q/2 on the other plate
D. Q/2 on each plate
E. Q on one plate and 0 on the other place.
Q2. The label on a light bulb says that it is rated at 75 watts. That means:
A. no matter what voltage is applied to the bulb, it will dissipate 75 W
B. the actual power dissipated will be much higher than 75 W because most of the power appears as heat rather than as light
C. the bulb is expected to “burn out” after its 75 watts are used up
D. when the proper voltage is applied to the bulb, it will dissipate 75 W
E. none of the above
Q3. A magnet moves inside a coil. Consider the following factors:
A. the strength of the magnet
B. the speed at which the magnet moves
C. the number of turns in the coil
Q4. Which can affect the emf induced in the coil?
A. I only
B. II only
C. III only
D. I and II only
E. I, II, III
Q5. Two light bulbs are labeled 100 watts and 60 watts. When installed in an ordinary household fixture, everyone knows that the 100 watt bulb is brighter than the 60 watt bulb. Could it be true that under certain circumstances a 60 watt bulb is brighter than a 100 watt bulb?
A. Yes, if wired in series the current through each bulb is the same, so the bulb with the higher resistance filament will consume more power and appear brighter.
B. Yes, if wired in series the voltage across each bulb is the same, but since the current is also the same the bulb with the lower rating appears brighter.
C. Yes, if wired in parallel the voltage across each is the same but since the current is shared, the lower resistance filament of the 60 watt bulb makes it appear brighter
D. Yes, if wired in parallel the current through each bulb is the same, so the bulb with the lower resistance filament will consume more power and appear brighter.
E. No, a 100 watt bulb always is brighter than a 60 watt bulb --- that’s why they are labeled that way.