SHM in Traveling Wave and Energy – Rankers Physics

Waves and its Characteristics: Practice Problem & Solution

Assertion (A): Every small part of string does SHM in sinusoidal travelling wave. Reason (R): In this small segment of string total energy is conserved.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Solution Explained:

To solve this problem, we apply the core principles of Waves and its Characteristics. Understanding the underlying formula is key to arriving at the correct answer below:

In a sinusoidal traveling wave, each particle of the string oscillates in simple harmonic motion (SHM) perpendicular to the direction of wave propagation. So, Assertion A is true. However, for a *traveling* wave, energy is continuously transmitted along the string. Therefore, the total energy within a small segment of the string is *not* conserved, as energy flows into and out of the segment. Reason R is false.

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