Wave Reflection at Free End – Rankers Physics

Standing Wave in String and Organ Pipe: Practice Problem & Solution

Assertion (A): When a pulse on string reflects from free end, the resultant pulse is formed in such a way that slope of string at free end is zero. Reason (R): Zero resultant slope ensures that there is no force component perpendicular to string.  
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

Short Solution (Best for NEET):

To solve this problem, we apply the core principles of Standing Wave in String and Organ Pipe. Understanding the underlying formula is key to arriving at the correct answer below:

At a free end, there's no transverse force, so the slope \( \frac{\text{dy}}{\text{dx}} = 0 \). The resultant pulse is formed such that the free end is a displacement antinode. This implies zero slope, ensuring no transverse force. Both Assertion and Reason are true, and R correctly explains A.

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