ShmoopTube

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And here's your shmoop du jour brought to you by enchanted

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forest unfortunately none of the forests around us have dragon eggs or dwarves.. one [Dwarf with a dragon egg in a forest]

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time we thought we found a treasure map though but it turned out to be a burger

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wrapper it did lead us to a good McDonald's though. Bognor the dwarf is

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foraging in the wire forest and stumbles across a dragon egg his first thought [Elf walks into a dragon egg]

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is to make a dragon omelet but his kinder nature prevails he decides to

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incubate the egg with a 60-watt light bulb which of the following statements

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is correct, select two answers and here the choices...... oh good old Bognar sure he may

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look grumpy on the outside but we know he's really happy inside yeah we're [Bognar dancing]

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going to work our way through all the seven dwarves here people so we can't

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let this opportunity slip by and it's nice of a Bognar to take care of this

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dragon egg, although we really wouldn't want a dragon hatching in [Dragon egg hatches and dragon appears]

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our place we're not big fans of flying fire hazards but if we do want to make

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this future dragon warmer we need to increase the power of the bulb. Power is a

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product of voltage and current so if we increase the voltage will crank up the

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power and crank up the heat and we bet all that warmth is making the dragon [Dragon egg by a burning fire]

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to be nice and sleepy, answer A is one of our correct choices right there if the

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voltage across the bulbs increased than the current through the both remain

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constant the heat emitted by the bulb will increase. Answer B says charge

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carriers have zero electric potential energy at the positive terminal of the

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battery but by convention charge carriers are positive which means at the [Positive carrier travelling down a road]

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positive terminal charge has the maximum electrical potential energy we're not

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too bashful to stand up and say B is wrong let's take a look at how power can [Person switches power button on]

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be expressed.. power or watts equal current or amps times voltage or volts and

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current AKA amps equals charge over time or coulombs over second so amps can be

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expressed as coulombs per second and volts can be expressed as well volts so

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yeah power can indeed be stated as both coulombs per second answer C gets

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clean bill of health from the doc it's one of the right choices and as for

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answers D well the electrons in in a current [Electrons in a current travel to negative]

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are negatively charged so they are repelled from the negative end of a

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battery like people are repelled from us when we get hay fever.. No one

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likes us when were sneezy.. So answer D is incorrect and there you have it four

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choices two correct answers and seven dwarfs wait we got all seven in their [Seven dwarfs appear]

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sorry sometimes we can be dopey about this kind of thing.

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