Physics Chapter 3 Questions | Sound

 KADHIM ADNAN sound Chapter three SOUND Question How do we define Sound wave? a longitudinal wave made of compressions and rarefaction that is caused by A...

 KADHIM ADNAN sound Chapter three SOUND Question How do we define Sound wave? a longitudinal wave made of compressions and rarefaction that is caused by Answer vibrations and travels through a material medium. Question What is compression? Answer Compressions it pushes the air particles in front of it closer together, creating a region of higher density and pressure. Question What is Rarefaction? Answer Rarefaction air particles close to each other become less crowded, creating a region of lower density and pressure. Question What is vibration? Answer A vibration is the complete back and forth motion of an object. Question What are the characteristics and characteristics of a sound wave? Answer ①Travel in all directions away from their source. ②Travels through all forms of matter gases, liquids and solid. ③ They travel fastest in solids, then liquids and slowest in gases. ④ Sound cannot travel through a vacuum. ⑤ Can't actually see sound waves, but they can be represented by spheres that spread out in all directions. Question Why are some sounds loud, soft, high, or low? Answer The differences between sounds depend on the properties of the sound waves. Question How the speed of Sound Can Change? Answer ① The speed of sound is increased by increased density of medium (solid, liquid, or gas) ② The speed of sound is increased by increased temperature of medium (solid, liquid, or gas) Secondry 2 1 07833844556  KADHIM ADNAN sound Question What is Reflection of sound waves? Answer is the bouncing back of a wave after strikes a barrier. Question What is Echo? Answer is a reflected sound wave. Question Why Sound waves easily reflect of a gymnasium? Answer Because gymnasium has a smooth hard wall. Question How is Echolocation? Answer The process of using reflected sound waves to objects. Used by animals such as bats, Beluga whales and dolphins. Question What is conditions Echo occurs? Answer ① The distance between sound source and reflecting surface must not be less than (17) meters. ② The time period between hearing the original sound and its echo should not be less than (0.1) s 1 *Echo can be used to measure the distance or the depth by: 𝑑=𝑠× 𝑠 2 Question On what basis, the echolocation depends? Answer depend on the how long it takes sound waves to echo back to the ears. Question What is Ultrasonography? Answer is medical procedure that uses echoes (to see) inside a patient's body without doing surgery. Question What is Sonar? Answer is a type of electronic echolocation. Question For what Ultrasonography used? Answer ① Is used to examine kidneys, gallbladders, and other organs. ② It is also used to cheek the development of an unborn baby in a mother's body. Secondry 2 2 07833844556  KADHIM ADNAN sound Question Why Ultrasonic waves are used instead of X rays? Answer ① Because their short wave lengths give more details about the objects they reflect off. ② Ultrasonic waves are less harmful to human tissue than X rays. Question What is Resonance when it's happens? Answer happens when an object vibrating near of a second object can make another object vibrate if they both have the same resonant frequency. Question What is Sound Quality? Answer The difference between music and noise does not depend on whether you like the sound. The difference has to do with sound quality. Question How do you distinguish between the violin sound and the piano sound? Answer could tell them apart because the instruments make different sounds. because a single note on an instrument actually comes from several different pitches. CHAPTER QUESTIONS Question Where can sound not travel? Answer Sound waves cannot travel through a vacuum. Question Choose the correct answer from the following: ① During a laboratory experiment about the nature of sound, Sara walked into a large, dark room and yelled "Hello" She heard a strong echo of the word almost immediately. Which of the following is a valid conclusion Sara could draw from her observations? A) The room has smooth, hard walls and few things in it. B) The room is bill of pillows and other soft objects. C) The room has no walls. D) The room is very cold. ② Sound travels fastest through: A) vacuum. B) sea water. C) air. D) glass. Secondry 2 3 07833844556  KADHIM ADNAN sound Question A man standing in front of a wall a way from him 360 m he sent a sound an heard it's echo after 2 sec. find the speed of sound? 𝑑 360 solution 𝑠= = = 360 𝑚/𝑠 𝑡 1 Question A man standing in front of a mountain sends a sound and hear it's echo after 2 sec. calculate the distance between the man and the mountain? (Consider the speed of the sound is 340 m/s) solution 𝑚 𝑑 = 𝑠 × 𝑡 = 340 × 1 = 340 𝑠 Question under what conditions does resonance occur? Answer Resonance: happens when an object vibrating near of a second object can make another object vibrate if they both have the same resonant frequency. Question Why do ultrasonic waves produce images of object inside the body effectively? Answer Because their short wavelengths can image small objects. Question Explain why the speed of sound in air depends on the temperature? Answer Because the Molecules that have more motion (more energy and higher temperature) can transfer their vibrations more easily. This is less noticeable in liquids and solids because the particles are closer together. Question Fill the empty box in the following table: Speed of sound in air ° Speed Temperature(𝐶 ) 0 𝑣 = 331 + 0.6𝑇 = 331 + 0.6(0) = 331 𝑚/𝑠 20 𝑣 = 331 + 0.6𝑇 = 331 + 0.6(20) = 343 𝑚/𝑠 25 𝑣 = 331 + 0.6𝑇 = 331 + 0.6(25) = 346 𝑚/𝑠 100 𝑣 = 331 + 0.6𝑇 = 331 + 0.6(100) = 391 𝑚/𝑠 Secondry 2 4 07833844556