WEBVTT
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in this question, the rocket is moving by injecting
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some mass off gas. We know that in the
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course off one second that rocket objected 1/1 60 off
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its mass and by doing that, it achieved an
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acceleration off 15 m per second squared. And with
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that we have to determine what is the velocity of
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the gas that is being expelled. To do that
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, we have to use this equation which relates the
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achieved acceleration which the velocity of the gas that is
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being expelled, the initial mass off the rocket to
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the variation in the mass off the rocket and the
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time during which that mass was expelled. So using
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that equation, we have the following they achieved acceleration
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is 15 m per second squared. Now we have
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minus the velocity off the gas which we don't know
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divided by the initial mass off the rocket which I
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will call em are Then we multiply it by the
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variation in the mass off the rocket. The variation
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in the mass off the rocket is equals to minus
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the mask off gas that was expelled. So we
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have minus the mask off the rocket divided by 160
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. And finally we divide by Delta T, which
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is one Then we get the following 15 is equals
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to we have a minus sign and another minus sign
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so they will cancel out. So we have the
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velocity of the gas divided by the mass off the
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rocket. Now, anything divided by one is just
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that thing. That minus sign isn't there anymore.
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So we have the mass off the rocket divided by
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160. As you can see, the mass of
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the rocket will be canceled. Then we get the
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following 15 is equals to the velocity of the gas
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divided by 160. The reform The velocity of the
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gas is 15 times 160 which results in 2000 and
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400 m per second or 2.4 kg meters per second
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. Any off those two is a correct solution to
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this question. So this is the answer