A student is shaking a flexible string attached to a wooden board in a rhythmic manner. Which of the following choices will decrease the wavelength within the rope? (a) The student could shake her hand back and forth with greater frequency.
(b) The student could shake her hand back in forth with a greater amplitude.
(c) The student could increase the tension within the rope by stepping backwards from the board. (a) I only
(b) I and II
(c) I and III
(d) II and III
(e) I, II, and III

Video Transcript

This is College Physics Answers with Shaun Dychko. So the student is shaking a string attached to a wooden board and they want to decrease the wavelength which is the same as increasing the frequency. From some experience with maybe a string denchment, you might know that increasing the tension in the string increases its frequency which is the same that it decreases the wavelength. So number three works. Number one also works because it is saying that they are increasing the frequency by shaking it more quickly. And so that also decreases the wavelength. And number two does not decrease the wavelength. That has no effect on it because it is not related to amplitude. So one and three are the answers. And so the answer is c.