Answer: = 340 3 = 1020m Which wave has a higher wavelength? taken on the y axis and time is taken on the x axis. A longitudinal wave is a wave in which the particles of the medium vibrate in a direction parallel to the direction of propagation of the wave. Wave motion is a type of motion in which the disturbance travels from one point of the medium to another but the particles of the medium do not travel from one point to another. Distance travelled = 60 + 35 = 95 km Displacement = 25 km O C represented on the distance time graph. b) f = \(\frac { n }{ t }\) = \(\frac { 2 }{ 4 }\) = 0.5 Hz If the farmer starts at the midpoint between two neighbouring square corners, his net displacement will be equal to the squares side, which is 10m. = 6 m The speed of sound in water is estimated to be 1500 m/s 2. Ultrasonography: Ultrasonic waves are used for getting images of internal organs such as kidney, liver, gall bladder and uterus. c) What is its velocity? The instruments shown below are working by making use of some sound phenomenon. Interference is the superposition of two waves of the same frequency travelling in the same direction. a) What is the amplitude of the wave? Answer: c = 3 x 108 m/s Examples: visible light, x-rays, infrared rays. intervals of time it is uniform acceleration. Wave Motion is the motion of the waves. Save my name, email, and website in this browser for the next time I comment. Whether all the particles are in the same phase of vibration at a particular time? (ii) Propagation of sound waves through air or any other material medium. Consider a particle P at a distance x from the particle O on its right. b) What is the frequency? Due to the high frequency of vibration of ultrasonic waves, dust and grease like substances get detached and are removed from the object. is called circular motion. Answer: If a sound wave travels 1700 m through a medium in 5 s. Identify the medium. Not only all living organisms exhibit motion, but non-living things . So distance between the source and reflecting surface = 1020/2 = 510 m All rights reserved. In a seismograph, the difference in the arrival time of the primary and secondary waves can be used to determine the approximate distance to the epicenter. What is the direction of propagation of particles in the medium when sound is travelling through air? So they do not reach the detectors. Selecting the right stream after class 10th plays a great role in making a successful career. aoe 5104 class 5 9/9/08 online presentations for next class: lecture 1 (introduction to class & periodic motion) lecture class 6 chapter 10 2020. What is Wave Motion? direction. time = 1/10 s Sample Test Waves and Sound Multiple Choice. For the propagation of wave, medium must have inertia and elasticity. The velocity of each particle is maximum at mean position and zero at extreme position. This is because the C for compressions and R for rarefactions. Difference Between Distance and Displacement, Deriving the Equation for Velocity Time Relation, Deriving Equation for Position Time Relation, Deriving the Equation for Position Velocity Relation. Interact one on one with top university representatives, apply with one click and secure on-spot offers and scholarships. (a) Its possible; an object launched into the air accelerates at a constant rate owing to gravity. V = 340 m/s There are two types of mechanical waves: b) Find out the wavelength? As waves approach the seashore, the trough of the waves rubs against the land. Question 3. body per unit time. t = \(\frac{\text { distance }}{\text { time }}\) Devices like megaphone, horns, musical instruments like shehnai and trumpets, are made in such a way that the sound produced form them travels only in a certain direction without spreading to other directions. The wave is formed in 2s. In this article, we will study the different types of waves in nature and their wave motion. waves formed when a rope is moved up and down after tying one of its ends. Sound waves involve the vibrations of the particle of the medium. The direction of motion of particles is perpendicular to the direction of propagation of the wave. Kerala Syllabus SAMAGRA SCERT SAMAGRA Question Pool for Class 9 English Medium Physics Wave Motion, The graph shown below gives the displacement and the distance travelled by a wave in 2 seconds, a. complete the table using the graph shown below, b. What is this phenomenon called? b) Loudness decreases, Question 19. Answer: One of the properties of a wave is that it replicates itself after an equal interval of length. b) one and half cycle in 90cm. If so, what will be the limit of wavelength of sound waves that are audible to human beings? \(\begin{array}{l}{\text { Frequency of the wave }=\frac{\text { number of vibrations }}{\text { time }}} \\ {f=n / t=\frac{100}{5}=20 \mathrm{Hz}}\end{array}\) = v/f = 17m velocity Acceleration = ------------------------------------- Time The principle of superposition of waves can be explained as: a. velocity of a body is a vector quantity involving both distance and __________________. BrainsPrep is one of the first Kerala Syllabus learning app started in 2017. b. Hello? Must Read: Class 9 Social Science- Natural Vegetation and Wildlife, Distance Time Graphs represents a change in position of the object with respect to time. We all know what a wave motion is. b) Creates pressure difference in the medium If we felt a boom of sound in empty rooms. Illustrate your answer Answer: The Gol Gumbas in Bijapur of Karnataka is another example. f) Forms crest and trough Mechanical waves: The presence of a medium is required for the transmission of these waves, eg. Velocity = \(\frac{\text { Distance }}{\text { time }}\) This is What is the speed of the wave if it travels 800 m in 2 s? Physics Wave Motion Class 12Notes : https://drive.google.com/file/d/1EfG-KeL9JibaT5hR4D-eji8Rbn537KKM/view?usp=drivesdkTimestamps :00:00 Introduction07:30 Ty. Crests are the positions where the wave is displaced from equilibrium by A. Wind a ribbon on the rope. parallel to OC. Velocity(kmh-1 ) X 10 30 50 10 15 20 t1 t2 A B C D Velocity time If the particles of the medium vibrate to the direction of the propagation of the wave, then the wave motion is called longitudinal wave motion. No, Question 9. The wave moves forward or horizontally. Acoustics of buildings is the branch of science that deals with the conditions to be fulfilled in the construction of a building for clear audibility. = 17 m, Question 27. does united have first class international; bring back kleptomancy. It will result in resonance and the window panes will start vibrating with higher amplitude. Question 7. Due to the variation in pressure at different region in the medium longitudinal waves are called pressure waves. Question 8. Then what is the velocity of the wave through the rope? distance moved or the displacement. Consider a velocity time graph for a body moving with uniform Motion can be described in terms of the uniform speed Y, b) Velocity time graphs :- The change in the velocity of a body All the particles in phase are at distance equal to n where n=1, 2, 3 and is the wavelength. Write down the relationship in the first pair of words. Mcq On Wave Motion Mcq On Wave Motion Simple Harmonic Motion with Examples Problems Visuals. asked Sep 23, 2021 in Physics by Waman (53.9k points) wave motion. c) Draw the graph of another wave with no change in the frequency and with half of its amplitude. NCERT Solutions for Class 9 Science Chapter 12 Multiple Choice Questions. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Get notified about the latest career insights, study tips, and offers at Leverage Edu. Answer: Or, Whether you are a school student or an employee, writing a leave application is a skill that you, All of us use different figures of speech in our everyday life, no matter which language we speak.. f = 2 kHz = 2000 Hz distance time graph for uniform speed is a straight line ( linear The waves which needs a medium for propagation are (light waves, Electromagnetic waves, mechanical waves, Radio waves). f = V/ What is Wave Motion When a particle moves through space, it carries KE with itself, wherever the particle goes, the energy goes with it. How many compressions are their in the longitudinal wave shown in the figure? = 1.5 km area of triangle ABD 1 = OA X OC + --- ( AD X BD ) 2 Substituting a) What is its amplitude? A wave is the disturbance produce in the medium from an equilibrium condition which travels with the finite velocity in the region of space.Wave motiontransfersenergy from one point to another, which may or may not displaceparticles of the medium. Answer: Since it takes some time for the disturbance to reach P, its displacement can be written as, Where is the phase difference between the particles O and P, Hence a path difference of x corresponds to a phase difference of 2x/=, Substituting the value of the in equation 2, ${\rm{y}} = {\rm{A\: sin}}\left\{ {\frac{{2{\rm{\pi t}}}}{{\rm{T}}} - \frac{{2{\rm{\pi x}}}}{\lambda }} \right\}$, ${\rm{y}} = {\rm{A\: sin}}\frac{{2{\rm{\pi }}}}{\lambda }\left\{ {{\rm{vt}} - {\rm{x}}} \right\}$ 4, Similarly, for a particle at a distance x to the left of O, the equation for the displacement is given by${\rm{\: y}} = {\rm{A\: sin}}\frac{{2{\rm{\pi }}}}{\lambda }\left\{ {{\rm{vt}} - {\rm{x}}} \right\}$, If the wave travels from right to left in negative x-axis then the equation for the displacement is given by, ${\rm{y}} = {\rm{A\: sin}}\frac{{2{\rm{\pi }}}}{\lambda }\left\{ {{\rm{vt}} + {\rm{x}}} \right\}$ 5. Answer: waves on water waves formed in a slinky waves formed when a rope is moved up and down after tying one of its ends. One of the reasons for the difference in the speed of sound is the difference in the density of the media. A person who bursts a cracker hears its echo after 1 s. What is the distance to the reflecting surface if the speed of sound in air is 340 m/s? E.g. Will you be able to hear the sound? At its core, it is a miniaturized superstring landscape and the energy release is not directly proportionate to its supersymmetry moduli, but . Q2. Find out the amplitude of the wave does not change with time. in equal intervals of time. How many crests and troughs are there in the figure? a) Is there any change for occurring echo? graphs :- The change in the position of a body with time can be So sound is travelled through air. Freshwater, Sydney, NSW 2096, Question 33. a) sound wave Motion can have different features like speed, direction, acceleration, etc. The ripples in water, the propagation of sound, the rays of light, are all examples of wave motion. What should be the minimum distance to the reflecting surface if the velocity of sound in air is 340 m/s? graph for a body moving with uniform velocity Y, ii) If a body whose velocity is increasing with time, the graph The amplitude of the waves, obtained using seismo-graph determines the intensity of an earthquake. Velocity V = f = 92 1 = 92 m/s. Write down examples of wave motion that you see around. What is the wavelength of the first wave? Write down examples of wave motion that you see around. Sound with a frequency greater than 20000 Hz, ie, above the higher limit of audibility is called ultrasonic sound. Kerala Syllabus SAMAGRA SCERT SAMAGRA Question Pool for Class 9 English Medium Physics Wave Motion Qn 1. fly. Wavelength = 4 m. Question 12. We come across thousands of moving things on a daily basis. a) Distance = Velocity time 1. Class 9 solutions in science is a beneficial reference and guiding solution that helps students clear doubts instantly, in an effective way. Yellow, black. Observe the wave motion on the rope. Speed = \(\frac { Distance travelled }{ time }\) . Hence Tsunami is not felt by passengers . the body between the points A and B with velocity 20 km h-1 s v = b) No Answer: c) 50 m, Question 13. Book a FREE counselling session today! The amplitude is less in the deep sea. supplementary-motion-record-of-the-class-action-plaintiffs class : 9 class : 9 mathematics class : 9 3 test assess class 37 wave motion class 37 wave motion author rishi topic 9: motion in fields 9.4 orbital motion, 1) Describing motion :- i) Motion :- is the change in position Whispering galley: Physics MCQ on Motion . Sound waves of wavelength 0.01 m. from a vibrating body reach your ear through air. What change takes place in the wavelength when the frequency increases? Class 9 Motion Important Equations. Observe the figure Amplitude : Amplitude is the maximum displacement of a particle from its mean position. Question 18. t1) s = AC X CD s = area of the rectangle ABDC 20 40 Time (s) Try to save your life and not your belongings, as life is precious. Selina ICSE Solutions for Class 9 Physics Chapter 8 Propagation of Sound Waves. f = 0.5 Hz In the bay region, the speed of Tsunami ranges from 600 to 800 km/h and their wavelength from 10 to 1000 km. When two waves having same frequency travelling in the same direction meet each other, constructive interference is formed. ii) Distance moved :- is the Uttar Pradesh 201301, Devonshire House, 60 Goswell Road, B: Reverberation C: Echo Question 31. Ultrasonic waves from a ship hits a rock at the bottom of the sea and comes back after 0.5 s. Calculate the distance to the rock from the ship. b) Sonar Answer: c) If the vibration of the rope is doubled what change will happen to the lenghth between A and B? Answer: The equations of motion represent the relationship between an object's acceleration, velocity and distance covered if and only if, The object is moving on a straight path. b) wavelength Q3. time ,t = 4s The Greek letter X (lambda) is used to denote the wavelength. = 1522 \(\frac { 0.5 }{ 2 }\) = 380.5 m. Question 36. The circumference of a circle of radius r is given by The angular frequency of a wave in SHM is, \(\omega\) = 2 \(\pi f\) The formula for waves Physics. SYLLABUS: 6. = 2 x 99 = 198 m Answer: b) By what name are sounds of such frequency known as? Hold the other end of the rope and move it up and down.The speed of the wave is constant. This change of position and movement is called - 'Motion'. = area OABC ( which is a trapezium ) = area of rectangle OABC + change in velocity). 3. Fill half of a trough with water. = 148.2/2 b) Write TWO methods, by which you can reduce the harmful effects of reflection of sound in big halls. a) What is known as the vibration of sound board of Guitar and air inside a Chenda? Answer: distance velocity time ----------------------- or 2as = v2 u 2 2a Time (s) Velocity(ms-1 ) The distance in Physics is the length of the direction (line or curve) defined by an object travelling through space. b) V = 6420 m/s Please verify. 5. We can see disturbance spreading from its origin to other place. 1. Sonar (Sound Navigation and Ranging): Sonar is a device that uses ultrasonic waves to measure the distance, direction, and speed of objects underwater. A sound wave generated in 4 seconds is shown in the graph. Rough surfaces can absorb sound. What is the velocity of the wave given above, Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 9 English Medium Tuition. Three seconds later, its echo was heard. Therefore in 3m 3/0.75 = 4. Let the wave travel with a velocity v from left to right. When we clap our hands from a field or valley having width greater the 17m, we can hear echo. = ------------------------- Time If the velocity of a body changes e. All points between two successive notes vibrate simultaneously. Motion can be described in terms of the distance moved or the displacement. initial position to its final position. A wave is the disturbance produce in the medium from an equilibrium condition which travels with the finite velocity in the region of space.Wave motion transfers energy from one point to another, which may or may not displace particles of the medium. c) Calculate the frequency of the wave if it took 0.2s to reach A. As frequency increases, wavelength decreases. If the body covers equal lengths in equal time intervals, so it is assumed to have a Uniform Motion. triangle ADE 1 s = AB X BC + --- ( AD X DE ) 2 A B 10 20 30 t1 t2 C A-258, Bhishma Pitamah Marg, Block A, Tsunami height depends on the geographical nature of the coast and the depth of the seabed. Velocity of sound in air is 340 m/s. 3. uniformly decelerated motion Velocity time graph for non uniform Each particle of the wave vibrates in a direction perpendicular to the direction of propagation of the wave. b) Loudness increases, Question 22. = 1482 1/10 Exercise 8(A) Solution 1S. Question 25. point B to the time and velocity axes so that the initial velocity = 3000 m Class 9 Atoms And Molecules Study Notes for students! A sound signal from a ship floating on water hits a rock at the bottom of the sea and comes back to the ship after 4s. b. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Kerala Syllabus 9th Standard Textbooks Solutions, Kerala Syllabus 8th Standard Textbooks Solutions, Plus Two Previous Question Papers and Answers, Plus One Previous Question Papers and Answers, Kerala Syllabus 9th Standard Physics Solutions, Kerala Syllabus 9th Standard Maths Solutions Chapter 1 Area, Kerala Syllabus 9th Standard Chemistry Solutions Chapter 6 Non-Metals, Kerala Syllabus 7th Standard Maths Solutions Chapter 9 Ratio, Kerala Syllabus 6th Standard Maths Solutions Guide, Kerala Syllabus 7th Standard Maths Solutions Guide, Kerala Syllabus 6th Standard Maths Solutions Chapter 4 Volume, Kerala Syllabus 6th Standard Maths Solutions Chapter 5 Decimal Forms, Kerala Syllabus 7th Standard Maths Solutions Chapter 6 Square and Square Root, Kerala Syllabus 6th Standard Maths Solutions Chapter 10 Letter Math, Kerala Syllabus 6th Standard Maths Solutions Chapter 6 Numbers, Kerala Syllabus 6th Standard Maths Solutions Chapter 7 Decimal Operations, Kerala Syllabus 6th Standard Maths Solutions Chapter 8 Joining Angles, Kerala Syllabus 6th Standard Maths Solutions Chapter 11 Statistics. Sound needs a material medium to travel. Two surface waves, Rayleigh waves that travel only through the Earths surface and Love waves, are also formed as a result of earthquake. Answer: If the position of an object varies over time, the object is considered to be in motion: Distance The distance covered by the object is defined as the complete length of the path covered by the object between the two endpoints. Sound is a vibration that typically arises from an object. f = 20000Hz, Answer: Frequency of the first wave, Question 16. s = area of trapezium OABC (OA + BC) X OC s = = 35 cm = 0.35 m = 148.2 m c) Find out the amplitude of the wave. You can Download Wave Motion Questions and Answers, Summary, Activity, Notes, Kerala Syllabus 9th Standard Physics Solutions Part 2 Chapter 7 help you to revise complete Syllabus and score more marks in your examinations. c) Where the wavelength will be more when a sound wave from a tuning fork of frequency 256Hz travels through air and steel? With respect to reflection of sound, what are the problems if the distance between the walls in a room is more than 17 m? i) If a body moves with uniform velocity, the graph will be a Hang some pieces of paper on the coils at equal distances. Discuss. We know V = f . Answer: b) Make the walls rough, provide a large number of ventilators. = 34m f = 330/60 = 5.5 Hz and reaches A and then moves back and reaches C through B, then Bhooming of sound is heard when the sound is produced in an empty hall. then the velocity v is given by 2r v = ---- t. in ships. a) Yes, can hear echo. Examples of these waves are: vibrations in strings, ripples on water surface and electromagnetic waves. Answer: travelled by the body between the points A and B is the area OABC. Here pressure difference is plotted against the y-axis. e) Seismic waves Here are the three important equations of the class 9 Motion chapter: Equation for Velocity . The vibrations of the tuning fork make the air particles around it to vibrate. b) The ceiling of certain halls are constructed with a curvature. a) The sound waves get reflected form the walls, ceilings, floor etc. Learn everything starting from the definition of motion, to its types, solved examples and question answers with these exclusive notes! Answer: The wavelength of sound traveling in air with the velocity 330 m/s was found to be 66 m. What should be the minimum distance between the source and the reflecting surface in water to identify the echo within water? Wave motion 6.1 Define and understand progressive wave 6.2 Write progressive wave in mathematical form 6.3 Discuss the condition under which stationary waves can be formed 6.4 Write stationary wave in mathematical form 6.5 Calculate frequency, amplitude, velocity, time period, etc of progressive wave To determine the distance travelled by The science of study of sound is acoustics of buildings. Sound getting reflected repeatedly from different objects is multiple reflection. 1. b) V = f Yellow, black. Tsunami is coined by combining two Japanese words Tsu which means harbor and nami .which means long wave. This creates compressions and rarefactions alternately in the medium. Required fields are marked *. In this case is the motion of particles parallel or perpendicular to the direction of propagation of the wave? i) The In this a) F The walls are made rough to avoid the regular reflection of sound. b) Distance traveled by the wave in 4 seconds. 4 compressions. 3. You would like a simple explanation of what moving like a wave is, so I need something to contrast with wave-like motion. Waves Review The Physics Classroom. (one way of transport energy from one place to another place). Regions of low pressure are the rarefactions (R). They are. Motion is all around us, from moving cars to flying aeroplanes. Question 8. O Velocity time graph for a uniformly accelerated motion t u v A B b. = 34000 Hz > 20,000 Hz b) What is the distance between these particles called? Barry? This is due to the multiple reflection of sound from the circular walls. It may be positive (+ ve) or negative (- ve). The waves which are responsible for the earthquake originate from the epic centre of the earthquake . As a result the speed and wavelength of the waves drop down suddenly, amplitude increases and the coastal region gets submerged. A medium is not essential for its propagation. 2021 brainsprep.com All rights reserved. Save my name, email, and website in this browser for the next time I comment. A wave is defined as a disturbance caused by the propagation of energy in space or a medium. b) ripples formed on the surface of water. Seismic waves formed as a result of earthquakes are classified into three: Primary waves (p waves), Secondary waves (S waves) and surface waves. How are these moving objects different from one another? 3. the particle behavior of the wave in time. These waves are then converted into electrical signals and are used to form images of the organs. b) The distance between source and receiver decreases (Model 2014) ii) Average velocity :- is the ratio of the total Question 24. Displacement Velocity = ------------------ Time b) Distance between A and D vector quantity. Another property of wave motion is that it is a method of transfer of energy. V = 198/0.6 Press a few coils on the free end held in the hand and then release Cant you explain why the disturbances on water could not make the paper boat move away from the shore? Answer: Time If a body travels a distance s in time t then its speed v is s Distance of the rock from the surface of water = 6000/2 m Observe the figure said to be in uniform motion. c) 1m. Answer: Question 14. 4. Answer: v = --- t The SI unit of speed is meter per second m/s or ms -1 or the rate of change of velocity.) V = 1500 m/s Question 13. a) 5 m = \(\frac { 1700 }{ 5 }\) = 340 m/s, Question 16. Distance travelled by the sound Delhi 110024, A-68, Sector 64, Noida, Block A, Defence Colony, New Delhi, a) Longitudinal wave (speed of sound in water is 1482 m/s) How does the ribbon/paper move? Answer: This is as a result of reverberation. The motion in a medium in which, when particles are displaced, a force proportional to the displacement acts on the particles to restore them to their priginal position is called an elastic wave. Thus, certain physical quantities that do not need guidance for their full definition are called scalars. straight line parallel to the x axis . A-258, Bhishma Pitamah Marg, where u - is the initial velocity v - is the final velocity a - is of displacement) of the body. speed :- is the ratio of the total distance travelled to the total a) what is the frequency of vibration of the table? Answer: (c) Question 2. = \(\frac { 1500 }{ 700 }\) = 2.14 s, Question 6. 4. of motion are :- i) v = u + at ii) s = ut + at2 iii) 2as = v2 u2 No medium required. = 1500 m This is denoted by the letter a. Wavelength: Wavelength is the distance between two consecutive particles which are in the same phase of vibration. What is the speed of the wave if its frequency is 92 Hz? --------------------------------, 3) Speed with direction :- The rate of motion of a body is more Echocardiography: Ultrasonic waves are used for taking images of heart. Ultrasonic waves passed through a metal block, are allowed to reach the detectors. The concept of motion is very important to understand higher concepts in physics. Question 1. Velocity of sound in water is 1482 m/s and velocity in air is 343 m/s. Answer: moves in a circular path with uniform speed, its motion is called c) Calculate velocity of the wave if it is traveled within 0.02 S. a. Answer: 3 .All the particles in the medium has same amplitude, frequency and time period. Class 9 Social Science- Natural Vegetation and Wildlife, Structure Of An Atom Class 9 Science Notes, End-to-end support for your study abroad journey, Distance provides the complete details of the path taken by the object, Displacement does not provide the complete details of the path taken by the object, Displacement can be positive, negative or zero, The distance between two points may not be unique, The displacement between two points is always unique. We provide free classes & study materials for Class 10 English Medium, Class 10 Malayalam Medium and Class 9 English Medium students. 1. moving in a straight line from origin O and moves through C and B 1. So, subscribe my channel and stay tuned for updatesSound#2-Characteristics of wave motion|Compressions. Pressure difference forms only in longitudinal waves a. A body is said to be in motion when its position changes with respect to a stationary object. These two properties of medium decide the speed of wave. d) V = 300 m/s a) what is the direction of motion of the particle P if the sound wave is travelling in the direction AB through the medium. United Kingdom, EC1M 7AD, Leverage Edu Answer: a) Amplitude of vibration decreases. b) What is the wavelength of the wave? c) Distance between A and B This is the expression of the progressive wave equation.