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Hello, everyone.
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So today we'll be doing problem number 18 from chapter 8.
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And this is asking for what the speed of the ball will be when it reaches basically the bottom of this pendulum.
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So let me draw it right now, right? so what do we have here? we have a string with a ball.
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And basically, this is the bottom.
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And the ball is going to pass through this.
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This point.
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This is the bottom.
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We have an angle here and that is 30 degrees.
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We have the length of this string being two meters.
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So two meters and we know that the mass of the ball is five kilograms.
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So mass is equal to five kilograms.
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And this is basically a reference from question number seven.
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So how do you do this problem, right? well, easy.
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Conservation of energy once again.
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So this is only two problems.
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Paria is asking for speed when it reaches the bottom.
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So what do we do? set up our conservation of energy equation, right? and which energies do we start with? well, the ball is at this position.
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It's elevated.
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There is separation.
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There is height.
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Obviously, it is gravitational potential energy.
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And obviously, when it reaches the bottom here, that's the fastest point...