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Question
Radius of a cylinder is r and the height is h. Find the change in the volume if the height remains same and the radius is halved.
Solution
∵ Volume of a cylinder = πr2h
Where, h is height and r is radius of base of the cylinder.
If height remains same and radius is halved.
i.e. h = h and `r = r/2`
∴ Volume = `pi xx r/2 xx r/2 xx h`
= `pi xx r^2/4 xx h`
Hence, volume became `1/4` th of the original volume.
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