Water in a conical flask with radius 7 cm and height 48 cm is poured into a cylindrical flask with radius 14 cm. The water level in the cylindrical flask is:
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Correct answer: D
Explanation
The correct answer is option 4 i.e 4 cm.
Volume of a cone = (1/3) × π × r² × h = (1/3) × π × 7² × 48 = (1/3) × π × 49 × 48 = (1/3) × π × 2352 = 784π cubic cm
Volume of cylinder = π × r² × h = π × 14² × h = π × 196 × h
The two volumes equal:
⇒ 784π = π × 196 × h
⇒ 784 = 196 × h
⇒ h = 784 / 196 = 4 cm