ShmoopTube

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Thank you We sneak then here's your shmoop du jour

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brought to you by experimenting with electricity which should be

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done very carefully We don't want to do an experiment

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that only teaches us that electricity can really hurt you

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Rather take sciences word for it Alright When electricity was

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first discovered it didn't have much practical use Electrician's quotes

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there such a stephen gray used it as a form

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of entertainment In seventeen thirty gray invented the flying boy

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experiment to show that the human body could conduct electricity

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In the experiment a boy was suspended from the ceiling

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by silk chords and his feet were attached to a

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charge generator We'll charge accumulated at the boy's feet and

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moved up to his hands Boy could now attract feathers

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or small slips of paper to his fingers and check

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out the following diagram That's what it looks like that's

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how they dressed back then it treats the boy and

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a feather as point charge is separated by two centimeters

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The boy has a charge of one micro coolum and

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the feather has a charge of four nano columns and

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a massive ten to the negative forthe kilograms use columns

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Law and newton's second law determined the acceleration experienced by

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the feather and hear the potential answers All right Okay

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Well when we were younger science class might have been

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a little more interesting and a lot more frightening if

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we've been wired to the ceiling with electrical current going

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through us apparently using small children as guinea pigs was

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cool back in the seventeen hundreds were kind of glad

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things are different now to solve this first we need

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to figure out the course that's acting between the boy

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and the feather will use coghlan's law for that Well

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cool ums Law states and an electric force between two

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objects equals the product of cool arms constant and the

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two charges use of one and use up to divided

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by the square of the distance between them Here's the

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equation All right In this case que ce of one

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will be the boy's charge and queues up two will

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be the feathers chart let's Plug in the numbers on

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top We have cool ums constant which will round up

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to nine times ten to the ninth newton meters squared

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for coolum square Then we have the charges for the

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boy he's got one times ten to the negative sixth

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fulham's running through him and the feather has four times

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ten to the negative Nine columns All that is over

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two tons ten to the negative Second meters squared You

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got some big numbers here but we're not scared of

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Big numbers were scared of clowns heights and rabbits but

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not big numbers All right when we do the math

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We get a force of nine times ten to the

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negative second newt okay now for the cool um let's

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move on to the next lawmaker who's even more old

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school than big c I would like that all right

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but figure out the acceleration will go with newton's Second

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law isaac newton says force equals mass times acceleration which

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means that acceleration equals force divided by mass But we

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just found the force nine times ten to the negative

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second news and we know the mass of the feather

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ten to the negative forthe kilogram Well when we plug

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in the numbers we find that the acceleration has nine

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times ten to the second meters per second squared or

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nine hundred meters per second squared That means he is

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the right answer and no matter how much our little

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brother annoys us we won't go all frankenstein on him 00:03:31.813 --> [endTime] way Want to be good scientists not mad one

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