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Let's do this question, the thickness of a hollow metallic cylinder is two centimeter.

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All right.

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If 70 centimetres long with outrageous 14 centimeter.

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OK, find the volume of the metal used in making the cylinder, assuming that it is open at both the

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ends.

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Also find its way if the metal weighs eight gram centimetre cube.

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All right.

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Pause the video, give it a try and then let's do it together.

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All right, we're back.

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Let's do it together.

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Now, over here we are having a hollow cylinder right now.

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Let's make a rough sketch of the cylinder mentioned over here.

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All right, now, over here, it's given that the outer radius is 14 centimeter.

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So I'm taking the outer edges as 14 centimeters and it's given that the thickness is two centimeters.

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Right.

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It's also mentioned that it's 70 centimeters long or this height over here is 70 centimeter.

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All right, now we know that the volume of this ship will be base area into height right now, what

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is the base area?

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That would be Pyaar Square minus by our square where this is the larger radius and then this is the

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smaller radius.

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But take this as R and this is smaller than the base area spy into our square minus our square.

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That's equal to Bindu 14 square.

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Minus 12 square.

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Right.

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Because this is equal to therefore this smaller radius will be equal to 14 minus two.

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That's equal to 12 centimeters.

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Right.

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So this base area becomes pi into 14 square, minus 12 square.

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And we know that the height is 70.

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Right.

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Therefore, the volume is equal to find 14 square minus 12 square in 270.

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That gives you 50 to buy into 70.

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All right, so let's simplify this, 52 into 22 by seven in 270.

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That's equal to one one four four zero centimetre cube.

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All right, so we need to also find the Veidt.

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Right, that's also asked we have found the volume right?

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That's the first part of the question.

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Now we need to find the weight of the metal weighs eight grams per centimetre cube.

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Now, we have found the volume of the hollow cylinder.

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Therefore, the weight will be one one four four zero into eight.

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That's equal to nine one five two zero gram.

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That is your answer.