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Question
Two cylinders with equal volume will always have equal surface areas.
Options
True
False
Solution
This statement is False.
Explanation:
Consider two cylinders with the following measures
E.g. r1 = 2 cm, h = 9 cm and r = 3 cm, h = 4 cm
For the first cylinder,
Volume = πr2h = π × 22 × 9 = 36 π cm3
Again, for the second cylinder,
Volume = πr2h = π × 32 × 4 = 36 π cm3
∴ The volumes are equal.
Now, surfaces area of first cylinder = 2πh = 2π × 2 × 9 = 36 π cm2
And surface area of second cylinder = 2πrh = 2π × 3 × 4 = 24 π cm2
Which are not equal.
So, the statement is false.
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