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All right And here's your shmoop douceur brought to you

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by tensions were talking about tension and physics Not about

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attention Watching your team playing game seven world series like

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have our fingernails seen better days Check the following diagram

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and passage right here you rocks lunch All right Your

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tree house has sweet system for bringing up food without

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making you descend your ladder A string connects two baskets

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over a massless pulley basket A resting ground level in

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basket b is at your front patio Yes You have

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a patio it's that suite when your mom comes by

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and puts luncheon lower basket you add rocks the basket

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b in order to live basket eh With heavier basket

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falls in lighter taste Your basket rises and voila Lunch

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is served Assume that the police frictionless that basket has

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a mass of two kilograms And basket b has a

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total mass of six kilograms Question What is the tension

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of the string as the baskets move All right i'll

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answer All right well just quick Heads up the answer

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this questions you're going to need to have answered the

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previous question first it's okay we'll wait You can't help

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But look for only back then Question three were so

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much younger than so vibrant But if today is just

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a random question work they don't worry about it One

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extra question won't hurt at least All right Now in

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order to calculate the force of tension on the string

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we need to take the product of one of the

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objects mass times gravity and added to the product of

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the objects mass times acceleration So if we use our

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lunches object one equation looks like this All right Because

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we already calculated the acceleration in the last question We

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have all the numbers we need to answer this one

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See your previous question Come in handy now Let's Plug

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in the numbers two kilograms times ten meters per second

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squared plus two kilograms times five meters per second squared

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It gives us thirty newtons Which means the correct answer

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is option deep But just to be sure let's plug

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in the numbers using basket be we might initially think

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that we come up with a different answer because basket

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b has a larger mass But remember basket b is

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moving away from us so it has negative acceleration Numbers

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would look like this 6 kilograms times ten meters per

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second squared plus six kilograms times negative five meters per

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second Squared equals thirty newtons about that what's the same

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No matter which object we use As long as we

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remember to use positive acceleration for an object moving towards

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us and negative acceleration for an object moving away from

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us If we study enough hopefully we can reduce the

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tension felt while waiting for ap physics test results Because

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our fingernails Well they just can't take it anymore I've 00:02:39.61 --> [endTime] been down to the bone

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