Explain the reflection of a wave at a free support.

(N/A) When a transverse wave pulse travels along a string and reaches a free end (a support that can move freely,such as a ring on a frictionless rod),it reflects back without any phase change.
$1$. As the pulse reaches the free end,the end is displaced to its maximum amplitude.
$2$. Because the support is free to move,it does not exert a restoring force in the opposite direction to the incident pulse.
$3$. Consequently,the reflected pulse has the same polarity (crest remains a crest) as the incident pulse.
$4$. There is no phase change of $\pi$ radians (or $180^{\circ}$) upon reflection at a free boundary.