Change set

Pick exam & year, then Go.

Question map
Not attempted Correct Incorrect Bookmarked
Loading…
Q51 (CAPF/2021) Science & Technology › Basic Science (Physics, Chemistry, Biology) › Quantitative aptitude topics Answer Verified

Eight metallic balls of one centimetre radius each are melted into one ball. The diameter of the new ball is

Result
Your answer:  ·  Correct: C
Explanation

To find the diameter of the new ball, we first calculate the total volume of the eight smaller metallic balls. The volume of a single sphere is given by the formula V = (4/3)πr³. Given each small ball has a radius (r) of 1 cm, the volume of one ball is (4/3)π(1)³ = (4/3)π cm³. Since there are eight such balls, their combined volume is 8 × (4/3)π = (32/3)π cm³. When melted into one large ball with radius R, its volume must equal this total: (4/3)πR³ = (32/3)π. Simplifying this equation, we find R³ = 8, which means R = 2 cm. The diameter of a sphere is twice its radius. Therefore, the diameter of the new ball is 2 × 2 cm = 4 cm.

How others answered
Each bar shows the % of students who chose that option. Green bar = correct answer, blue outline = your choice.
Community Performance
Out of everyone who attempted this question.
43%
got it right
✓ Thank you! We'll review this.

SIMILAR QUESTIONS

5 Cross-Linked PYQs

UPSC repeats concepts across years. Login to see how this question connects to 5 others.

Login with Google