WEBVTT
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in question. A. We have to calculate the
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orbit of speed V oven electric around a protein given
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that the radius. But this is between the election
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and the problem is 10 to the minus 10 meters
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. Uh, and we have to do that using
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the electric static force. We know that the electrostatic
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forces, even between an electron approach, is getting
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by k times the chart of the elections square time
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divided by the radio square. And since the electron
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is moving in a circular motion, this is equal
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to end v squared over R, where m is
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the mass of the electorate. And from here you
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got the V is equal to e times the square
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root of K over in our, so you can
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substitute the numbers. Here he is one point c
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six times sent to the minors 19 Coombs times the
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square root of K, which is nine times 10
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to the ninth Newtons meters per square Brooklyn square divided
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by the mass of the electron, which is 9.1
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times 10 to the minus 31 kilograms. Times are
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, which is 10 to the minus 10 meters.
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So this is equal to 1.6 times 10 to the
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sixth. Neither is per second. This is the
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answer to question a in question be we have to
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. We have to decide whether we should use Ah
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, this special relativity theory when dealing with this with
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the electric at this speed that we calculated in question
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, they and we know that whether we should or
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used a special relativity or not depends on the value
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of beta, which is defined as of you oversee
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, because if it is much smaller than one,
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then we shouldn't use special relativity. Okay, And
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let's see if, in our case view ever see
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, is much more than what. So let's go
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play. Beta beta is able to 1.6 times said
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to the six meters per second, which is our
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speed divided by this bit of life, which is
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three times 10 to the eight meters per second.
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And this is approximately five times said of the minus
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three, which is much smaller than one. Then
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we don't need to use, uh, special relativity
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. Okay, in questions. See, we have
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to calculate the really wavelength off the electoral, and
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we know that the Beverly Wavelength Lunda is people to
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h over the momentum of the particle. And since
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our particles known relativistic as I just explained in question
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be the momentum is just envy. And let's insert
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numbers. You're so ages 61 63 times in the
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minus 34 Jules Second I m is the mass of
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the electron, which is 9.1 time sentinel minus 31
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kilograms and V is 1.6 times 10 to the sixth
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meters per second, which is equal to 4.5 time
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. Stand to the minus 10 meters. Hey,
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this is the wavelength literally wavelength of the election.
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And in question D, we have to check whether
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we should expect the fraction phenomenon interference phenomena, Uh
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, given that the wavelength of the electric is 4.5
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times 10 to the minus 10 meters and what we
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should notice is that the radius of the atom itself
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, the size of the atom is actually I'm not
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gonna write our I'm gonna write just d. That's
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the side of the atom. It's about 10 to
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the minus 10th meters. Okay, that's the So
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that's the typical size of the atoms. Tend to
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the minister and the wavelength of the electorate is of
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the order is about. In this case, it's
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equal to 4.5 times into the minus 10 meters.
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Okay, so notice that the to both the size
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of the Adam and the wavelength of the election are
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about the same size. They have the same order
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of magnitude. And for that reason we can expect
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to see wave phenomena happening with the Elektrim, such
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as interference and diffraction. So here the question is
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yes to