Physics · Mechanical Properties of Matter

JEE Main 2026 — 4 April, Morning Shift — Question 20

The surface tension of a soap solution is 3.5×10⁻² N/m. The work required to increase the radius of a soap bubble from 1 cm to 2 cm is α×10−6\alpha\times10^{-6} J. The value of α\alpha is ______. (π=22/7\pi=22/7)

Answer: 264

Numerical answer — enter this value.

Step-by-step solution

Work = 2T×4π(r₂²-r₁²) = 2×3.5×10⁻²×4π×(4-1)×10⁻⁴ = 2×3.5×4π×3×10⁻⁶ = 84π×10⁻⁶ = 84×(22/7)×10⁻⁶ = 264×10⁻⁶ J ⇒ α=264

Answer key and solution verified before publishing.

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Exam
JEE Main 2026
Subject
Physics
Chapter
Mechanical Properties of Matter
Topic
Surface Tension and Surface Energy
The surface tension of a soap solution is 3.5×10⁻² N/m.… | JEE Main 2026 PYQ with Solution · DhiX AI