A string with a fixed frequency vibrator at one end is undergoing resonance with 4 antinodes when under tension T1. When the tension is slowly increased the resonance condition disappears until tension T2 is reached, there being no resonances occurring between these two tensions. How many antinodes are there in this new resonance?
A)3
B)4, since all resonances in this situation have the same number of nodes
C)5
D)2, since resonances only involve whole wavelengths
E)6, since resonances only involve whole wavelength

Question

Quizplus · Accepted Answer

The correct answer is A.When the tension is increased, the wavelength of the standing wave decreases. This means that the number of antinodes must also decrease. Since there are 4 antinodes at tension T1, there must be 3 antinodes at tension T2.

A String with a Fixed Frequency Vibrator at One End