ExamBro
ExamBro
JEE Mains · Physics · STD 11- Mechanical properties of solids
  • JEE Mains 2026
  • Easy
  • MCQ

The speed of a longitudinal wave in a metallic bar is \(400~m/s.\) If the density and Young's modulus of the bar material are increased by 0.5% and 1% respectively then the speed of the wave is changed approximately to ___________ \(m / s\).

Pick an option to check your answer.
Verified Solution

Answer & Solution

Correct Answer

(D) 401

Step-by-step Solution

Detailed explanation

\(V_{sound}=\sqrt{\frac{Y}{\rho}}\)
\(\frac{\Delta V}{V}\times100=\frac{1}{2}(\frac{\Delta Y}{Y}\times100)-\frac{1}{2}(\frac{\Delta\rho}{\rho}\times100)\)
\(=\frac{1}{2}\times1-\frac{1}{2}\times0.5\)
\(\frac{\Delta V}{V}\times100=\frac{1}{4}\)
\(\Delta V=\frac{1}{4}\times\frac{V}{100}\)
\(\Delta V=1m/s\)
\(V_{final}=400+1=401~m/s\)
Same subject
Explore more questions on app
From JEE Mains
Explore more questions on app