Question 1: Sound is a type of wave that travels through a medium by causing particles to vibrate. The properties of these waves determine how we perceive sound in terms of pitch, loudness, and quality. Understanding these properties is essential in various scientific and technological applications.

Answer: Sound properties include pitch, loudness, and timbre, which are determined by the frequency, amplitude, and waveform of the sound wave respectively.

Question 2: Define 'pitch' in relation to sound waves.

Answer: Pitch is the perception of how high or low a sound is, which depends on the frequency of the sound wave.

Question 1: Explain how the amplitude of a sound wave affects its perceived loudness.

Answer: A larger amplitude increases the energy of the wave, resulting in a louder sound perceived by the human ear.

Question 2: What is the typical range of frequencies that humans can hear?

Answer: Humans can typically hear frequencies from about 20 Hz to 20,000 Hz.

Question 1: A sound wave in air has a frequency of 440 Hz and a wavelength of 0.78 meters. Calculate the speed of sound in air under these conditions.

Answer: Speed = 440 Hz × 0.78 m = 343.2 m/s

Question 2: If the speed of sound in steel is approximately 5000 m/s, what is the frequency of a sound wave with a wavelength of 1 meter in steel?

Answer: Frequency = 5000 m/s ÷ 1 m = 5000 Hz

Question 1: Describe a simple procedure to measure the frequency of a sound wave using a smartphone application. Include safety precautions and variables to control.

Answer: Use a smartphone app designed for frequency analysis by recording the sound in a quiet environment. Ensure the microphone is unobstructed. Control variables such as distance from the sound source and ambient noise levels. Keep the phone steady during recording to ensure accurate measurements.

Question 2: Identify at least three variables that can affect the accuracy of measuring the loudness of a sound in an experiment.

Answer: Microphone sensitivity, background noise, distance from the sound source.

Question 1: A recorded sound has a measured frequency of 1000 Hz and an amplitude that corresponds to a loudness of 80 decibels. Explain how changing the amplitude would affect the decibel level perceived.

Answer: Increasing the amplitude would increase the decibel level, making the sound appear louder; decreasing it would reduce the decibel level and perceived loudness.

Question 2: A sound wave with a frequency of 200 Hz is perceived as a lower pitch compared to a wave at 2000 Hz. Explain why this is the case.

Answer: Because pitch perception depends on frequency, with lower frequencies corresponding to lower pitches, the 200 Hz wave produces a lower pitch than the 2000 Hz wave.

Question 1: Describe how understanding the properties of sound is important in designing concert halls.

Answer: Designers use knowledge of sound reflection, absorption, and diffraction to ensure sound quality, clarity, and even distribution throughout the hall.

Question 2: Explain how the properties of ultrasound are used in medical imaging.

Answer: Ultrasound uses high-frequency sound waves that reflect off tissues to produce images, allowing for non-invasive diagnosis of internal body structures.