Sound：練習題

When a guitar string is plucked, it moves back and forth very quickly. This movement creates sound. What is the scientific term for this back-and-forth movement?

A student vibrates a ruler against the edge of a desk. If the student shortens the part of the ruler hanging over the edge and plucks it with the same force, how will the sound change?

Through which of these states of matter does sound usually travel the fastest?

A student observes that when a tuning fork is struck and held near a bowl of water, ripples form on the surface. What can be concluded about the production of sound from this observation?

A student sets up an investigation with three identical tuning forks. Tuning fork A is struck lightly, tuning fork B is struck with more force, and tuning fork C is placed in a vacuum. Which of the following statements about the amplitude and sound is correct?

A student uses a signal generator to increase the frequency of a sound wave coming from a speaker. How does this change the pitch of the sound heard by the student?

Why is it that we can hear a sound around a corner even if we cannot see the person who is speaking?

How does the thickness of a string on a violin affect the pitch of the sound it produces when plucked with the same tension?

Sound
A student is investigating how sound travels through different materials. They set up three containers: one filled with air, one with water, and one with a solid block of wood.

(a) In which container will the sound travel the fastest? Give a reason based on the particles in that state of matter.
(b) Define the term amplitude and explain how it affects the volume of a sound.
(c) If a sound has a high frequency, what will be the characteristic of its pitch?

Sound
An alarm clock is placed inside a glass jar. As the air is gradually pumped out of the jar to create a vacuum, the sound of the alarm becomes quieter until it cannot be heard at all.
(a) Explain why the sound disappears when the air is removed.
(b) Through which of the three states of matter (solid, liquid, gas) does sound typically travel the slowest?
(c) If a person puts their ear against a solid wooden table while someone taps the other end, will the sound be clearer than through the air? Why?