The mass of an aluminium rod varies directly with its length. If a 16 cm long rod has a mass of 192 g, then find the length of the rod whose mass is 105 g.

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

8.75 cm

8.00 cm

8.50 cm

8.25 cm

answer is A.

(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

Given the mass of an aluminium rod varies directly with its length and a 16 cm long rod has a mass of 192 g.
We need to find the length of the rod whose mass is 105 g.
Assume that length of the rod whose mass is 105 g is

l

cm.
Use the given fact that mass of an aluminum rod varies directly with its length hence ratio of mass and length would be constant.

\frac{mass}{length} = constant

Equate the ratio of 192 g mass and 16 cm length with ratio of 105 g with

l

cm to solve, for

l

\frac{105}{l} = \frac{192}{16}

\frac{105 \times 16}{192} = l

\frac{105}{12} = l

\frac{35}{4} = l

\Rightarrow l = 8.75

Length of the rod whose mass is 105 g is 8.75 cm.
Hence, the correct option is 1.

Result Producing online coaching for JEE/NEET of south India

Largest All India Test Series for JEE/NEET

Best Books for IIT JEE

Best Books for NEET

How to Join IIT after 10th

Best Courses for You

JEE

NEET

Foundation JEE

Foundation NEET

CBSE

Get Expert Academic Guidance – Connect with a Counselor Today!

Result Producing online coaching for JEE/NEET of south India

Largest All India Test Series for JEE/NEET

Best Books for IIT JEE

Best Books for NEET

How to Join IIT after 10th