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प्रश्न
Radius of a cylinder is r and the height is h. Find the change in the volume if the height is doubled and the radius is halved.
उत्तर
∵ Volume of a cylinder = πr2h
Where, h is height and r is radius of base of the cylinder.
If height is doubled and the radius is halved,
i.e. h = 2h and `r = r/2`
∴ Volume = `pi xx (r/2) xx (r/2) xx 2h`
= `pi xx r^2/4 xx 2h`
= `(pir^2h)/2`
Hence, volume became half of the original volume.
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