4. Waves and Optics
Sound — Quiz
Test your understanding of sound with 5 practice questions.
Practice Questions
Question 1
A sound wave is traveling through a medium. If the frequency of the sound wave is doubled while its speed remains constant, what happens to its wavelength?
Question 2
A sound source emits sound with a power of $100 \text{ W}$. What is the intensity of the sound at a distance of $10 \text{ m}$ from the source, assuming the sound propagates uniformly in all directions?
Question 3
An ambulance siren emits a frequency of $1000 \text{ Hz}$. If the ambulance is moving towards a stationary observer at a speed of $30 \text{ m/s}$, and the speed of sound in air is $340 \text{ m/s}$, what is the perceived frequency by the observer?
Question 4
A tube open at one end and closed at the other (a closed organ pipe) has a fundamental frequency of $150 \text{ Hz}$. What is the length of this pipe if the speed of sound in air is $340 \text{ m/s}$?
Question 5
The sound intensity level of a whisper is approximately $20 \text{ dB}$. How many times more intense is the sound of normal conversation, which has an intensity level of approximately $60 \text{ dB}$?