A cylindrical vessel of diameter 4 cm is partly filled with water, 300 lead balls are dropped in it. The raise in water level is 0.8 cm. Find the diameter of each ball.
Answer & explanation
Correct answer: option 2
Volume of 300 spherical balls = Volume of rise in water level
$⇒300×\frac{4}{3}×\frac{22}{7}×(\frac{d}{2})^3=\frac{22}{7}×2×2×\frac{4}{5}$
$⇒d=\frac{2}{3}=0.4cm$