WEBVTT
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So here we have a fan. The initial the
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initial angular velocity of the fan is going to be
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five hundred rpm. So revolutions per minute and then
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the final velocity is going to be two hundred rpm
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and then Delta T, this occurs in four point
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zero zero seconds. So they want us to find
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the angular exploration and the final displacement so we can
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say angle acceleration equals Omega final minutes. Um,
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an initial over Delta T. This is going to
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be equal to weaken, say, two hundred.
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This gonna be on RPM so we can cut.
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We have to convert it and say, one minute
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over sixty seconds and then we can say minus five
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hundred rpm again, one minute over sixty seconds.
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And at this point, we can divide the entire
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thing by four seconds. This is going to give
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us negative one point two five revolutions per second squared
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. And then at this point, we confined the
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angular displacement by saying that angular to spaceman is Eagle's
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angular, just initial angular displacement, plus initial angular
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velocities. Times t plus I have Alfa t squared
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and weaken. I actually canceled this out because the
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initial anger displacement is zero. And at this point
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we can just plug in. So we'LL say I'm
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using twenty five. Rather I'm doing twenty two hundred
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divided by sixty, which is going to be twenty
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over six or ten over three Or rather, my
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apologies That's final. So it would actually be five
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hundred divided by sixty, which would be twenty five
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over three. And then this would be times if
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four seconds and then it would be plus one over
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it, too. Native, one point two five
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force where'd and it is going to be twenty three
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point three revolutions. So this would be your two
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answers for partner get a new workbook. So the
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part be there, asking us How long? How
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much longer would it take for the entire thing to
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come to a full stop? So we can say
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that Omega Final equals Omega initial plus Alfa T and
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we can say we wanted to come to a full
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stops. We can say that's going to be zero
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. And then we in the Omega initial weaken say
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Okay, there's going to be simply rearranged to solve
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time and then plug in for negativo. Make initial
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. It's gonna be twenty five or three all over
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. Negative one point two five. There's going to
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be six point six six seven seconds. It was
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already going for four seconds, so T needed would
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be equal to six point six six seven minus four
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or two point six six seven seconds. So this
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would be time needed in order in order for the
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fan to stop motion hearted. And that's the end
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of the solution. Thank you for watching.