WEBVTT
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this question is not difficult to solve, but we
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have. You have to be quite smart about how
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can you think about it? So what I'm doing
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here is the following We wanted at her mind,
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for instance, in the first item, the tension
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in the coupling between the car number 30 on the
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car number 31. So what happens in the situation
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is that we have 30 cars pulling 20 cars,
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and this is the connection that happens between the car
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number 30 on the car number 31 and then to
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complete distention is quite a straightforward exercise. We just
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have to applying Newton's second law on either this car
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set or these car set. I choose to apply
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Newton's second law on these cars set by doing that
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to get the following. It says that the Net
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Force I'm also applying Newton's second law on this direction
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, which I'm calling the axe direction. So the
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net force in that direction is the course to the
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mass times acceleration off the object. There is only
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one force acting on that object to the right direction
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, and that only force is this tension. So
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the tension force is the course. True, the
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mass off that set off 20 cars so 20 times
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the mass off each car times the acceleration off that
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ah sent off cars. Using the information that we're
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given in the problem, we get attention. That
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is equals to 20 times 6.8 climb standard. The
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third times eight times 10 to the minus Truth.
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This is 20 times eight times 6.8 times 10.
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So the tension is approximately 1.1 time Stand to the
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fourth new terms in the situation. On the other
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situation, we have only one car that is push
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it by 49 cars. Applying Newton's second law of
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that single car, we get the following and that
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forces because of the mass off that single car times
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its acceleration, the net force is attention force.
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And then these easy questions. 6.8 times 10 to
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the third times eight times Stand to the miners Truth
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. These is 6.8 times eight times 10. These
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results, in attention off approximately 5.4 time stand to
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the second new terms