Sound (ध्वनि) Ch(11) Practice Quiz in Hindi Part – 2 || Class 9 Science Practice Quizzes in English Posted on February 28, 2025February 28, 2025 by Anshul Gupta0% 0 votes, 0 avg 1 Sound (ध्वनि) Ch(11)Practice Quiz in Hindi Part – 2 || Class 9 Science Practice Quizzes in English 1 / 201. Echocardiography is a technique that uses: A. Ultrasonic waves B. Light waves C. Ordinary sound waves D. Infrasonic waves Explanation: It is used to create images of the heart by analyzing the reflected ultrasound waves. 2 / 202. A hearing aid: A. Amplifies sound waves B. Increases the speed of sound C. Produces sound D. Reduces reverberation Explanation: It helps people with hearing loss to hear sounds more clearly. 3 / 203. Which of the following statements is NOT true about sound waves? A. They are longitudinal waves. B. They are produced by vibrating objects. C. They can be reflected. D. They can travel through a vacuum. Explanation: Sound waves require a medium to propagate.4 / 204. Which of the following animals can hear ultrasound? A. Elephants B. Humans C. Bats D. Dogs Explanation: Bats use ultrasound for navigation and hunting. 5 / 205. Which of the following is NOT a characteristic of a sound wave? A. Medium B. Speed C. Amplitude D. Frequency Explanation: While sound needs a medium to travel, the medium itself is not a characteristic of the sound wave. The characteristics of a sound wave are frequency, amplitude, and speed. 6 / 206. Ultrasonography is used for: A. Cleaning objects B. Detecting cracks in metal blocks C. Breaking kidney stones D. Examining the foetus during pregnancy Explanation: It helps to detect any abnormalities in the foetus. 7 / 207. The loudness or softness of a sound is determined by its: A. Frequency B. Amplitude C. Speed D. Pitch Explanation: A larger amplitude corresponds to a louder sound. 8 / 208. The quality or timbre of sound helps us to: A. Distinguish between sounds of different frequencies B. Determine the speed of sound C. Distinguish between sounds of the same frequency and amplitude but from different sources D. Distinguish between sounds of different amplitudes Explanation: Timbre allows us to differentiate between the sound of a guitar and a piano playing the same note. 9 / 209. Ultrasonic waves are used to detect cracks in metal blocks because: A. They have a high frequency and can be reflected by small defects B. They travel slower than ordinary sound waves C. They can bend around corners D. They are audible to humans Explanation: Ordinary sound waves would diffract around the cracks, making them difficult to detect. 10 / 2010. Frequencies higher than 20 kHz are called: A. Audible sound B. Supersonic sound C. Infrasound D. Ultrasound Explanation: Ultrasound has various applications in medicine and industry. 11 / 2011. The ceilings of concert halls are often curved to: A. Ensure even distribution of sound B. Focus sound in a particular direction C. Reduce reverberation D. Increase the speed of sound Explanation: The curved shape helps to reflect sound waves to all corners of the hall. 12 / 2012. Which of the following is NOT an application of ultrasound? A. Cleaning delicate objects B. Measuring the depth of the ocean C. Detecting earthquakes D. Imaging internal organs Explanation: This is typically done using sonar, which utilizes sound waves within the audible range. 13 / 2013. Breaking kidney stones into fine grains using sound waves is called: A. Lithotripsy B. Echocardiography C. Ultrasonography D. Sonoluminescence Explanation: This technique uses focused ultrasound waves to break the stones. 14 / 2014. The audible range of sound for human beings is: A. 0 Hz to 10 Hz B. 25 kHz to 50 kHz C. 10 Hz to 10000 Hz D. 20 Hz to 20000 Hz Explanation: This is the range of frequencies that most humans can hear. 15 / 2015. Ultrasound is used for: A. All of the above B. Detecting cracks in metal blocks C. Cleaning objects D. Medical imaging Explanation: Ultrasound has a wide range of applications due to its ability to travel along well-defined paths and penetrate various materials. 16 / 2016. The SI unit of frequency is: A. Second B. Hertz C. Meter D. Pascal Explanation: Hertz (Hz) is equivalent to cycles per second. 17 / 2017. The speed of sound in a medium is highest in: A. Liquids B. Vacuum C. Gases D. Solids Explanation: The closer the particles of the medium, the faster the sound wave can be transmitted. 18 / 2018. The pitch of a sound is determined by its: A. Loudness B. Speed C. Frequency D. Amplitude Explanation: A higher frequency corresponds to a higher pitch. 19 / 2019. A sound of single frequency is called: A. Noise B. Note C. Pitch D. Tone Explanation: A musical note is composed of multiple tones. 20 / 2020. Sounds of frequencies below 20 Hz are called: A. Audible sound B. Infrasound C. Supersonic sound D. Ultrasound Explanation: Infrasound is used by some animals for communication. Please insert your information to see your ranking अपनी Ranking जानने के लिए कृपया अपनी जानकारी भरे NamePhone Number Your score isThe average score is 35% 0% Restart quiz Category: Class 9 Science Quizzes in English