Banner 0
Banner 1
Banner 2
Banner 3
Banner 4
Banner 5
Banner 6

Q.

A spherical ball of lead, 3 cm   in diameter is melted and recast into three spherical balls. The diameter of two of the balls are 1.5 cm   and 2 cm   respectively. The diameter of the third balls is


see full answer

Talk to JEE/NEET 2025 Toppers - Learn What Actually Works!

Real Strategies. Real People. Real Success Stories - Just 1 call away
An Intiative by Sri Chaitanya

a

2.4 cm  

b

2.5 cm  

c

2.7 cm  

d

2.8 cm   

answer is B.

(Unlock A.I Detailed Solution for FREE)

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test

Detailed Solution

It is given that the diameter of the big spherical ball is 3cm .
So, the radius is 1.5 cm .
The diameter of two of the balls are 1.5 cm, and 2 cm respectively.
So, the radii are 1.5 2  cm,   , and 1 cm respectively.
Volume of the sphere is,
V= 4 3 π r 3  , where r   is the radius of the sphere.
The volume of the big spherical ball will be the sum of the volumes of the new three balls.
So,
V= V 1 + V 2 + V 3 4 3 π r 3 = 4 3 π r 1 3 + 4 3 π r 2 3 + 4 3 π r )3 3 r 3 = r 1 3 + r 2 3 + r 3 3 1.5 3 = 0.75)  
Solving further,
r 3 3 = 0.75 3 + 1 3 1.5 3 r 3 = 0.75 3 + 1 3 1.5 3 3 r 3 = 1.953125 3 r 3 =1.25  
Thus, the diameter is, 2.5 cm.
Therefore, option (2) is correct.
 
Watch 3-min video & get full concept clarity

Best Courses for You

JEE

JEE

NEET

NEET

Foundation JEE

Foundation JEE

Foundation NEET

Foundation NEET

CBSE

CBSE

score_test_img

Get Expert Academic Guidance – Connect with a Counselor Today!

whats app icon