The number of lead balls, each 3 cm in diameter , that can be made from a solid lead sphere of diameter 42 cm is:
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 2744
Radius of sphere = 42/2 = 21cm.
The radius of a lead ball = 3/2
In this case, volume remains the same,
The volume of the sphere = volume of n lead balls
4/3 × × 21 × 21 × 21 = n × 4/3 × × 3/2 × 3/2 × 3/2
n = 2744.