ABC26GN5053 · Volume and Surface Area
Subject: General Aptitude · Chapter: Volume and Surface Area · Exam: · Marks: · Difficulty:
A hemisphere of lead of radius 6 cm is cast into a right circular cone of height 75 cm. The radius of the base of the cone is
(a)1.4 cm
(b)2 cm
(c)2.4 cm
(d)4.2 cm
Answer
Explanation
Let the radius of the cone be $R$ cm. Then, $\frac{1}{3} \pi \times R^{2} \times 75=\frac{2}{3} \pi \times 6 \times 6 \times 6$ $$\Leftrightarrow R^{2}=\left(\frac{2 \times 6 \times 6 \times 6}{75}\right)=\left(\frac{144}{25}\right)=\left(\frac{12}{5}\right)^{2} \Leftrightarrow R=\frac{12}{5} \mathrm{cm}=2.4 \mathrm{cm} .$$
Open in whiteboard · Browse this chapter in the app