Q. 74.0( 142 Votes )
If each edge of a cube is doubled,
(i) how many times will its surface area increase?
(ii) how many times will its volume increase?
(i) ∵ Surface Area of a Cube SA= 6(Side)2
If Side is doubled then New Surface Area,
SA' = 6(2×Side)2
= 4× 6(Side)2
= 4 × SA
∴ SA of new Cube will be 4 times of SA of Original Cube.
(ii) ∵ Volume of a Cube V= (Side)3If Side is doubled then New Volume of Cube,
V'= (2× Side)3
= 8× (Side)3
= 8× V
∴ Volume of new Cube will be 8 times the Volume of Original Cube.
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