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प्रश्न
If the radius of a cylinder is doubled and the height remains same, the volume will be
विकल्प
doubled
halved
same
four times
उत्तर
Let V1 be the volume of the cylinder with radius r1 and height h1, then
`V_1 = pi r_1^2 h_1`……. (1)
Now, let V2 be the volume after changing the dimension, then
`r_2 = 2r_1 , h_2 = h_1`
So,
`V_2 = pi r_2^2 h_2 = pi xx (2r_1)^2 xx h_1`
`⇒ V_2 = 4 xx pi r_1^2 h_1 = 4V_1`
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