Q. In question, the shape of the wave at time$t = 3s$,if O is a fixed end (not free) in is.
A) [image:15_image3.emf]
B) [image:15_image4.emf]
C) [image:15_image5.emf]
D) [image:15_image6.emf]
Explanation
(a) When O is a fixed end, the formation of reflected pulse is equivalent to overlapping of two inverted pulses travelling in opposite direction as shown in figure.
Here at $t = 3\ s$, net displacement of all particles of the string will be zero ie the string will be straight as shown in figure.
[image:15_image52.emf]
Choice (a) is correct.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.