Two lightbulbs, one rated 60 W in ~ 120 V and also the other rated 100 W at 120 V, are arranged in two various circuits.

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1. Calculation the resistance of every bulb.

Answer:

, for this reason

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because that the 60 W bulb.

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for the 100 W bulb.

2. Explain what the 60 W and 100 W ratings mean.

Answer: The bulbs are designed to be associated directly to a 120 V source. As soon as you operate the bulbs as designed, they will dissipate the rated power. If castle dissipate an ext than the rated power, castle are most likely to burn out.

3. Which of the complying with quantities identify the brightness of a lightbulb?

Answer: c. Power

4. Which of the complying with quantities should be the very same for each pear in a series circuit?

Answer: a. Current

5. If both lightbulbs are connected in parallel to a 120 V source, i m sorry is brighter? explain your prize briefly.

Answer: The pear rated at 100 W will be brighter. As soon as both bulbs are connected to the rated voltage, they will certainly dissipate the rated power. The brightness the a bulb counts on the power it dissipates, so the 100 W bulb will be brighter than the 60 W bulb.

6. If both lightbulbs are linked in parallel to a 50 V source, which is brighter? Explain.

Answer: now the bulbs will certainly each it is in dimmer than once they\"re connected to 120 V. But the 100 W bulb will certainly still it is in brighter. No issue what a pear is connected to, its resistance is a residential or commercial property of the bulb. Parallel bulbs must take the exact same voltage. By the equation for strength , the bulb through the lower resistance will dissipate an ext power. The 100 W bulb has actually a smaller sized resistance, therefore it will certainly be the brighter bulb.

7. If both lightbulbs are linked in series to a 120 V source, which is brighter? Explain.

Answer: Bulbs linked in series each take it the exact same current. Power is also given through the equation P = I2R. With the same current, the bulb v the bigger resistance will certainly dissipate more power. Due to the fact that the 60 W bulb has the bigger resistance, it will be brighter.

8. Rank the brightness the the adhering to bulbs, through 1 gift the brightest and also 4 gift dimmest. Justify your answer through an explanation and/or a calculate in the space below.

Calculate the power dissipated by every bulb.

Answer: ___60 W bulb associated to 50 V source

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___100 W bulb linked to 50 V source

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In series: The equivalent resistance that the 2 bulbs in collection is 380W. When connected to 120 V, the present in the circuit is

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. This same present flows with both bulbs.

___ 60 W pear in collection with 100 W bulb and also 120 V source

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___ 100 W pear in series with 60 W bulb and also 120 V source

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Now rank follow to power dissipated:

4 (10 W) 60 W bulb linked to 50 V source2 (18 W) 100 W bulb associated to 50 V source1 (25 W) 60 W pear in collection with 100 W bulb and also 120 V source3 (14 W) 100 W bulb in collection with 60 W bulb and 120 V source

9. Explain briefly why, in your house, a 100 W bulb will constantly be brighter 보다 a 60 W bulb.

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Answer: In a house, all electrical outlets are linked in parallel to 120 V. Bulbs the you purchase in the store space rated for use on a standard family members 120 V circuit. For this reason if you plug her lamps right into a typical outlet, you constantly use the bulbs at their rated voltage and thus at their rated power. A 100 W bulb at home will constantly dissipate much more power 보다 a 60 W bulb and also so will always be brighter.