This seeming contradiction occurs on most physics tests. But it's true, and here's why:
Lamp A by itself has power of P=IxE ; 60=IxE ; so I=60/220=0.27 amperes. Thus the lamp has a resistance E=IxR ; R=220/0.27 = 807 ohms.
Lamp B by itself has a power of P=IxE ; so I=100/220 = 0.45 amperes. Thus the lamp has a resistance E=IxR ; R=220/0.45 = 489 ohms.
Since the resistance in series is added up, the total resistance is 807+489 =1296 ohms and the current I= E/R = 220/1296 = 0.17.....
Phew... Since P= IxIxR
For 60W lamp A, P= 0.17 x 0.17 x 807 = 23.3 watts.
For 100W lamp B, P=0.17 x 0.17 x 489 = 14.1 watts.
So, when they are wired in series, the bright one and the dim one appear to be reversed as to their respective "normal rated powers".
Their normal rated powers are only correct when both of them are supplied with their normal rated voltage of 220 volts, i.e. when they are wired in parallel. This makes a lot of sense if you think about it.
The lamps will get dimmer. In a parallel circuit, voltage is constant. Whereas, in a series circuit, amps are constant.
They can be connected to either supply. A bulb in series that fails, will cause all the other bulbs to go out. A bulb in parallel that fails, will have no adverse effect on the other bulbs in that circuit
No. They are connected in parallel with each other.
Adding additional lamps has no effect on the supply voltage supplied to you home. If the lamps are connected in series, then the sum of voltage-drops appearing across each lamp will equal the supply voltage. If the lamps are connected in parallel, then the voltage across each lamp will equal the supply voltage.
This question is the wrong way round. Assuming you the light bulbs are identical, they are brighter when connected to the power source in parallel than in series. This is because each bulb uses the entire potential difference of the power source, whereas in series, the bulbs act as potential dividers, reducing the voltage across the others and therefore the current passing through all of them.
Lamps connected in parallel are subject to the same voltage. Provided this voltage corresponds to the lamps' rated voltage, then each lamp will operate at its rated power and at its full rated brightness.Individual lamps connected in series operate below their rated voltage (the sum of the voltage drops around a series circuit equals the supply voltage) and will, therefore, operate below their rated power and brightness. The lamps will vary in brightness; those with the lower power ratings will be brightest and those with the higher power ratings will be least bright.
In parallel, they both obviously have 220 v across them, so the 100 W bulb is obviously brighter than the 60 W one. The 60 W bulb has more resistance, and in series they both have to pass the same current, so the 60 W has more voltage across it and might be brighter.
Parallel circuit.
because they are connected in series.
If you are referring to house wiring, then you don't normally connect lamps in series with each other; they are normally connected in parallel with each other. When lamps are connected in parallel, each lamp is subjected to the same voltage; providing this is the rated voltage of each lamp, them each will operate at their rated power.If you did connect lamps in parallel, the you would find that the lamps with the higher power ratings will be dimmer than the lamps with the lower power ratings -which is not what you might expect!
Because in series they split the voltage. Two resistors in series have half the voltage. In parallel they have the same voltage and draw current according to their individual resistance.AnswerFor a lamp to operate at its rated power, it must be subject to its rated voltage. For example, two 120-V lamps will operate at full power when connected in parallel across a 120-V supply, because each branch of a parallel circuit is subject to the same supply voltage.If the same lamps were connected in series across a 120-V supply, each would be subject to a voltage drop of 60 V, resulting in each lamp burning dimly.However, two identical 120-V lamps would operate at full rated power if connected across a 240-V supply, because the voltage drop appearing across two identical lamps will be 120 V. However, if the two lamps had different power ratings (and, therefore, different resistances), one voltage drop would be higher than the other, causing one lamp to burn brighter than the other. Since the lamp with the higher power rating has the lower resistance, the greater voltage drop would appear across the lower-power lamp which would burn brighter than the higher-power lamp.
-- Connect the cells in series. The two terminals of their series combination present a potential difference of 4 volts. -- Connect both lamps in parallel between the terminals of the series-connected cells.
The lamps will get dimmer. In a parallel circuit, voltage is constant. Whereas, in a series circuit, amps are constant.
They can be connected to either supply. A bulb in series that fails, will cause all the other bulbs to go out. A bulb in parallel that fails, will have no adverse effect on the other bulbs in that circuit
series
Circuit B
No. They are connected in parallel with each other.