WEBVTT
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we begin discretion by calculating the acceleration off this person
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when the tension is the maximum possible. So we
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were using that Newton's second law. Then let me
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set up my reference frame as everything that is pointing
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up. It's positive, and everything that is pointing
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down is negative. Newton second bald and tells us
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that the net force is equal to the mass off
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the man times his acceleration. The net force is
9
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composed in the situation by true forces, the maximum
10
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tension force and the weight force. And these is
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equal to the mass off the man times his acceleration
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. These is 569 minus 520. These results in
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49. Now to calculate the mass off that men
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we can use his weight No lotus that the wait
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Is it close to the mass times acceleration of gravity
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, Then the mass is the weight divided by the
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acceleration of gravity. So the mass off that man
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is equals to 520 divided by 9.8 times a and
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his acceleration is given by 49 divided by 520 divided
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by 9.8, which is a close to 49 times
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9.8 divided by 520 days, is approximately 0.9 to
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treat meters per second squared. Now that you know
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his acceleration, we can calculate the time it takes
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for him to clean that hope up to 35.1 meters
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. Remember that the distance is the cost of the
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initial position, plus the initial velocity times that time
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plus the acceleration times time squared, divided by truth
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In the situation, we can set up his initial
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height to be close to zero on his final height
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to be 35.1, then 35.1. Zico's too.
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His knees are position is zero. His initial velocity
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is also equal to zero because he departs from for
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arrest. Then this is a T squared divided by
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truth. Therefore, he squared. Is it close
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to two times 35.1? Divided by eight, these
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is 70 point true divided by eight. So he
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is equals to the square it off 70.2, divided
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by 0.923 and these results in approximately 8.7 seconds