WEBVTT
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for this problem. We have two parts and they're
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both asking is basically the same thing. So for
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part A, we're being asked, determined to determine
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the average angular velocity of mega as the earth spins
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on its axis. So to find Omega, we
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have a displacement in angle over a time. And
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if those if the angular velocity is constant, we
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can just take the total displacement and divided by the
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total time to find that angular velocity. So that's
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what we're gonna do for these problems. So for
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spinning on its axis, the earth rotates once per
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day. So the total angle displaced is going to
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be two pi radiance. And if we work in
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radiance and seconds, then we'll get an answer and
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readings per second, which is what we're looking for
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. So the total time involved in one day is
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24 hours times 3600 seconds per hour. So when
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we calculate this out, we get seven point 27
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times 10 to the minus five radiance per second and
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the way that I did this calculation here is one
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day is 24 hours. So if we want to
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insert something that is equivalent to one day and the
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denominator there, then we can do. Then we
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can put in 24 hours times 3600 seconds her,
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our and then the hours cancel, and we're left
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with 24 times 3600. So that's part a now
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for Part B. We need to do the same
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thing, but with a different amount of time.
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Because we have one full revolution. So are Delta
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Theta that we need to put in two this equation
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. It's still too piratey ins, but in this
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case we have one year for orbit around the sun
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. So in order to do this one one year
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is equivalent to 365 0.25 days. Okay, times
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a fraction with day on the bottom one day so
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that we can cancel the days in each day.
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There's 24 hours, and in each one hour there's
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3600 seconds. So if we multiply all this out
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will cancel our days. Well, cancel our hours
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and we'll have a number that's in seconds. So
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if we insert these numbers into a calculator for a
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year, we get 31 point six 1,000,000 seconds But
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if we just plug all these numbers directly into the
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equation above, where we end up getting is our
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answer for Omega, here is about two times 10
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to the minus seven radiance per second.