ShmoopTube

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Here's your shmoop du jour brought to you by doubling the size

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of the planet and we thought our backpacks were helping out all right [Boy carrying an oversized backpack on a school bus]

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well if the mass of the earth suddenly doubled in size what would happen to the

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strength of the gravitational force and here the potential aims we have

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double or quadruple okay if we went with our gut and just thought [mans belly popping his shirt open]

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well if mass doubles then gravity must double too, right? well then we'd be

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correct yes and the correct answer is option C but there's math that supports

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our brilliant intuition here so let's check it out gravity equals the [Floating mathematical equations]

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gravitational constant multiplied by mass divided by the square of the radius

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of the sphere in this equation the gravitational constant is represented by

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a big G if we double the mass then we'll have 2m rather than just m and when

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we distribute the 2 we get this so we don't need to worry about plugging in

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the actual numbers for now as long as we understand how the map actually works [A plug going into a socket]

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another way to look at it well force equals mass times acceleration right

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double the mass you get double the force and that's how we can prove that our

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initial thought is in fact correct the good news about a planet twice the size [Planet Earth doubling in size]

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well math is still math the bad news yep we'd weigh twice as much and we've heard

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about the freshman 15 but oh this is ridiculous... Heyy!

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