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Karnataka Board PUCPUC Science Class 11

The transverse displacement of a string (clamped at its both ends) is given by y(x, t) = 0.06 sin (2πx/3) cos (120 πt). All the points on the string between two consecutive nodes vibrate with ______.

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Question

The transverse displacement of a string (clamped at its both ends) is given by y(x, t) = 0.06 sin (2πx/3) cos (120 πt). All the points on the string between two consecutive nodes vibrate with ______.

  1. same frequency
  2. same phase
  3. same energy
  4. different amplitude.
Fill in the Blanks
Short/Brief Note
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Solution

a, b and d

Explanation:

Given equation is `y(x, t) = 0.06 sin ((2pi)/3 x) cos (120 pit)`

Comparing with standard equation of stationary wave `y(x, t) = a sin(kx) cos(ωt)`

It is represented by the diagram,

Where N denotes nodes and A denotes antinodes.

a. Clearly, frequency is common for all the points.

b. Consider all the particles between two nodes they are having the same phase of (120 πt) at a given time.

c. and d. But are having different amplitudes of `0.06 sin ((2pi)/3 x)` and because of different amplitudes, they are having different energies.

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Chapter 15: Waves - Exercises [Page 108]

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NCERT Exemplar Physics Exemplar [English] Class 11
Chapter 15 Waves
Exercises | Q 15.15 | Page 108

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