Exhibit 18-1
The figure below shows wave crests after a stone is thrown into a pond. Use this exhibit to answer the following question(s).
-Refer to Exhibit 18-1. The phase difference in radians between points A and D is
A) π.
B) 2π.
C) 3π.
D) 4π.
E) 5π.

Question

Exhibit 18-1
The figure below shows wave crests after a stone is thrown into a pond.  Use this exhibit to answer the following question(s).
-Refer to Exhibit 18-1. The phase difference in radians between points A and D is
A) π. 
B) 2π. 
C) 3π. 
D) 4π. 
E) 5π.

Quizplus · Accepted Answer

Points A and D are on opposite sides of a wave crest, which corresponds to a phase difference of π radians. The crest-to-crest distance between A and D is two wavelengths, which corresponds to a phase difference of 2π radians. Therefore, the total phase difference between points A and D is 3π radians.

Exhibit 18-1 The Figure Below Shows Wave Crests After a Stone Is