Two children are at opposite ends of an aluminum rod. One strikes the end of the rod with a stone. Find the ratio of times taken by the sound wave in air and in aluminum to reach the second child.

Question:

Answer:

Velocity of sound in air v₁= 346 ms^–1

Velocity of sound in aluminum v₂ = 6420 ms^–1

Let the length of the aluminum pipe = x m.

∴ Time = distance/velocity

Time taken in the air = xm / 346ms^-1

Time taken in the air = x / 346s

Time taken in aluminum = xm / 6420ms^-1

Time taken in aluminum = x / 6420s

Required ratio = x / 346s ÷ x / 6420s

⇒ x/346 x 6420/x

= 18.55

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Chapter 11

Question:

Answer:

Class 9 Important Questions

NCERT Solutions for Class 9

Chapter 11

Question:

Answer:

Class 9 Important Questions

NCERT Solutions for Class 9

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