A long string is constructed by joining the ends of 2 shorter strings. The tension in the strings is the same but string I has 4 times the linear mass density of string II. When a sinusoidal wave passes from string I to string II:
A) the frequency decreases by a factor of 4
B) the frequency decreases by a factor of 2
C) the wave speed decreases by a factor of 4
D) the wave speed decreases by a factor of 2
E) the wave speed increases by a factor of 2

Question

Quizplus · Accepted Answer

The wave speed in a string is given by $ v = \sqrt{\frac{T}{\mu}} $, where $ T $ is the tension and $ \mu $ is the linear mass density. Since the tension is the same and string I has 4 times the linear mass density of string II, the wave speed in string II will be twice that in string I.

A Long String Is Constructed by Joining the Ends of 2