WEBVTT physics/ap-physics-1-2/fullerton
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Hi everyone. I am Dan Fullerton. Welcome back to Educator.com.
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What we are going to do now is we are going to work through a series of worksheets that are fairly basic level problems, not quite at the level of the AP Physics exam that we are preparing you for, but it gives you an idea if you have the basic concepts down.
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If these go well, it is great to keep moving on, but if you struggle with these, it is probably an excellent opportunity to go back to some of the previous videos and review them and make sure you get the basic concepts down.
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We will just do the first page of each of these sheets.
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Starting with metric estimation -- and you can find a link to download it at the bottom of the page -- we will look at Number 1.
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What is the approximate width of a person's little finger?
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A little finger is about 1 cm wide, which could be 0.01 m.
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Number 2 -- The approximate mass of an automobile...?
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A hundred kilograms is about the mass of a pretty big person -- 10^6 kg is humongous, so let us go with 10³ kg, or about a 1000 kg or on the order of 2,000 lbs.
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The diameter of a United States penny...?
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Draw a penny, measure its diameter, and you should find out that again, you are starting to talk in the range of about 1 cm, which is 10^-2 m.
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Number 4 -- We are going to drop an egg from a third-story window and the distance the egg falls from the window to the ground is closest to...?
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If we assume that each story is about 3 m or 3 yards in the English system -- they are pretty close to each other -- that is going to be 9 m or 10 m for 3 stories, so 10¹ m, which is pretty close.
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The approximate height of a 12 oz. can of root beer...?
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A root beer is about that tall and compared to a meter, it is about 1/10 of a meter or somewhere in that ballpark, so I would say that it is about 0.13 m or Answer 2.
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Number 6 -- The mass of a paper clip...?
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The mass of a paper clip is going to be about 1 gram, which is 1/1,000 of a kg, so the correct answer there is 1 × 10^-3, which puts you in the right sort of ballpark.
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Number 7 -- The length of a dollar bill, the length of paper currency...?
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It is something like that -- about how much is that -- about 1/10 or maybe a little bit more of a meter, so of our answer choices, this one is the closest -- about 0.15 m.
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Number 8 -- What is the approximate length of a baseball bat?
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A baseball bat is about a meter long, so that is going to be 10^0, which is 1 m or Answer 2.
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What is the approximate diameter of an inflated basketball?
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Well, it is going to be less than a meter and maybe 20% of a meter or 0.2 m, so that will give us Number 2, 0.2 m is about the diameter of an inflated basketball.
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Number 10 -- The length of a football field...?
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The length of a football field or soccer field, I think is about 100 m, but which of these is closest to that?
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The top one here is 10 m, 1,000 cm, and 1,000 decimeter -- that is 100 m, so that must be our correct answer, Number 2.
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That covers page 1 of metric estimation.
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Thanks so much for your time and make it a great day everyone!