Concepts Of Physics MCQ Edition [Volume 1]PhysicsWave Motion and Waves on a String
Mark out the correct options.
Options
- AThe energy of any small part of a string remains constant in a travelling wave
- BThe energy of any small part of a string remains constant in a standing wave
- CThe energies of all the small parts of equal length are equal in a travelling wave
- DThe energies of all the small parts of equal length are equal in a standing wave
Correct answer
B. The energy of any small part of a string remains constant in a standing wave
Step-by-step solution
In a travelling wave, energy is continuously transmitted along the string. The energy of a small part of the string in a travelling wave fluctuates with time, as its kinetic and potential energy densities are maximum at the mean position and zero at the extreme position. Hence, option 1 is incorrect. Since the energy density is non-uniform at any given instant, all small parts of equal length do not possess equal energies in a travelling wave. Hence, option 3 is incorrect. In a standing wave, energy is confined wit