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This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 251. |
Given below are some examples of wave motion. State in each case, if the wave motion is transverse, longitudinal or a combination of both?(a) Motion of a kink in long coil spring produced by displacing one end of the spring sideways.(b) Wave produced in a cylinder containing a liquid by moving its piston back and forth.(c) Waves produced by a motor boat sailing in water.(d) Light waves travelling from the sun to the earth.(e) Ultrasonic waves in air produced by vibrating quartz crystal. |
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Answer» (a) The wave motion is transverse, because the vibrations of particle (kink) of the spring are at right angles to the direction of the propagation of wave. (b) The wave motion is longitudinal, because the molecules of the liquid vibrate to and fro about their mean positions along the direction of propagation of the wave. (c) The given motion is a combination of longitudinal and transverse waves. (d) The wave motion is transverse, because the light waves are electromagnetic waves in which electric and magnetic fields vibrate in the direction at right angle to each other and also to the direction of propagation of the wave. (e) Ultrasonic waves produced by a quartz crystal in air are longitudinal because the molecules of air vibrate to and fro about their mean positions along the direction of propagation of wave due to the vibration of quartz crystal. |
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| 252. |
We can not hear echo in a small room. Explain why? |
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Answer» The minimum distance between a source of sound and the obstacle to produce an echo should by 17 m. Since, the length of the room is generally less than 17 m, so we do not hear echo in the room. |
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| 253. |
If a sound wave travels from air to water, the quantity that remain unchanged is ……. (a) velocity (b) wavelength(c) frequency (d) amplitude |
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Answer» Correct answer is (c) frequency |
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| 254. |
When sound waves travel from air to water, which of the following remains constant? (a) velocity (b) frequency (c) wavelength (d) all of these |
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Answer» Correct answer is (b) frequency |
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| 255. |
With the increase in temperature, the frequency of the sound from an organ pipe (a) decrease (b) increase (c)remains unchanged(d) Changes erractically |
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Answer» (b) increase Frequency ∝ v/L. Now v and L both increase with temperature but increase of v is much more than the increase of L which is negligible . Thus frequency increases with temperature. |
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| 256. |
When sound waves travel from air to water, which of these remains constant? (a) velocity (b) wavelength (c) frequency (d) all the above |
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Answer» Correct answer is (c) frequency |
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| 257. |
In the resonance tube experment, the first and second states of resonance are observed at 20 cm and 670 cm. find the value of end correction (in cm). |
| Answer» Correct Answer - 3 | |
| 258. |
Two open organ pipes vibrating I their fundamental mode produces 5 beats per second. Find the number of beats produced per second if the temperature of medium is made 2.56 times and the pipes still vibrate in their fundamental modes. |
| Answer» Correct Answer - 8 | |
| 259. |
Figre shows photograph of a string vibrating in certain mode. Length of the string is 3 m. at the moment when photograph is taken particle at A was travelling upwards. |
| Answer» Correct Answer - A::B::C::D | |
| 260. |
The equation of a plane progressive wave is `y=Asin(pit-(x)/(3))`. Find the value of A for which the wave speed is equal to the maximum particle speed. |
| Answer» Correct Answer - 3 | |
| 261. |
A sonometer wire resonates with a given tuning fork forming standing waves with five antitodes between the two bridges when a mass of `9kg` is suspended from the wire. when this same tuning fork forming three antitodes for the same positions of the bridges. the value of `M` isA. (a) `25kg`B. (b) `5kg`C. ( c ) `12.5kg`D. (d) `1//25kg` |
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Answer» Correct Answer - A (a) `f_(0) = (5)/(2l)sqrt((9g)/(mu)) = (3)/(2l)sqrt((Mg)/(mu))` rArr `M = 25 kg` |
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| 262. |
The ends of a stretched wire of length `L` are fixed at `x = 0 and x = L`. In one experiment, the displacement of the wire is `y_(1) = A sin(pi//L) sin omegat` and energy is `E_(1)` and in another experiment its displacement is `y_(2) = A sin (2pix//L ) sin 2omegat` and energy is `E_(2)`. ThenA. (a) `E_(2) = E_(1)`B. (b) `E_(2) = 2E_(1)`C. (c) `E_(2) = 4E_(1)`D. (d) `E_(2) = 16E_(1)` |
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Answer» Correct Answer - C ( c ) `E prop A^(2)v^(2)` where `A = amplitude and v = frequency`. Also `omega = 2piv rArr omega prop v` In case 1 : `Amplitude = A and v_(1) = v` In case 2 : `Amplitude = A and v_(2) = 2v` :. `(E_(2))/(E_(1)) = (A^(2)v_(2)^(2))/(A^(2)v_(1)^(2)) = 4` rArr `E_(2) = 4E_(1)` |
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| 263. |
Two pulses in a stretched string whose centres are initially 8 cm apart are moving towards each other as shown in the figure. The speed of each pulse is 2 cm/s. After 2 second, the total energy of the pulses will be A. zeroB. purely kineticC. purely potentialD. partly kinetic and partly potential |
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Answer» Correct Answer - B The two pulses are moving towards each other. The speed of each pulse is 2 cm/s. `therefore` After 2 sec, one pulse moves to left by 4 cm and other pulse moves to right by 4 cm. `therefore` They superpose and annul the displacement of each other. The string will become straight. Hence there will be no potential energy. `therefore` The total energy of the pulses will be kinetic. |
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| 264. |
Transverse waves are produced in a stretched wire. Both ends of the string are fixed. Let us compare between second overtone mode (in numerator) and fifth harmonic, mode (in denominator). match the following column-I with column-II |
| Answer» Correct Answer - A::B::C::D | |
| 265. |
Distinguish between stationary wave and progressive wave. |
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Answer» 1. A stationary wave is formed by the superposition of two equal progressive waves travelling in opposite directions whereas, a progressive wave is formed due to continuous vibration of the particles of the medium. 2. The wave does not travel in any direction in stationary waves whereas, in progressive waves, the wave travels with a certain velocity. 3. There is no flow of energy in stationary waves whereas, in progressive waves, there is a flow of energy. 4. Particles at the node are at rest in stationary waves whereas, in progressive waves, no particles in the medium are at rest. 5. In stationary waves, amplitude is different for different particles, whereas in progressive waves, amplitude of all the particles is the same. 6. In stationary waves, all particles in a loop are in the same phase and they are in opposite phase with respect to particles in adjacent loops, whereas in progressive waves, phase changes continuously from particle to particle. |
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| 266. |
What are the beats? Define beat frequency. Explain how the frequency of a tuning fork is determined using beats. |
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Answer» The periodic rise and fall (Waxing and waning) in the intensity of sound due to the superposition of two sound waves of slightly different frequencies traveling in the same direction is called beats. The number of beats heard per second is called the beat frequency and is equal to the difference in the frequency is of the two sound waves. To determine the unknown frequency of a tuning fork Step 1: Consider a tuning fork A of known frequency f and another fork B of unknown frequency f'. When A and B are sounded together let m beats are heard/sec, ∴ f' = f ± m Step 2: Let one of the prong of B is loaded with a bit of wax. The two forks are again sounded together and let m be the number of beats heard/sec. f m’ > m, i.e. betas increases after adding wax, then real frequency of B is = f – m If nr’ < m, i.e. betas decreases or remains same after adding wax, then real frequency of B is f' = f + m. |
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| 267. |
A wave travelling in positive X-direction with `A=0.2m` has a velocity of `360 m//sec` if `lamda=60m`, then correct exression for the wave isA. `y=0.2 sin 2pi (6t+ x/60)`B. `y=0.2 sin pi (6t+ x/60)`C. `y=0.2 sin 2pi (6t-x/60)`D. `y=0.2 sin pi (6t-x/60)` |
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Answer» Correct Answer - d |
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| 268. |
When two waves of almost equal frequencies `v_(1)` and `v_(2)` reach at a point simultaneously, the time interval between successive maxima isA. `upsilon_(1)+upsilon_(2)`B. `upsilon_(1)-upsilon_(2)`C. `1/(upsilon_(1)+upsilon_(2))`D. `1/(upsilon_(1)-upsilon_(2))` |
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Answer» Correct Answer - D When two waves of almost equal frequencies `upsilon_(1) and upsilon_(2)` reach at a point simultaneously, beats are produced. Beat frequency,`upsilon_(beat)=upsilon_(1)+upsilon_(2)` Time interval between successive maxima `=1/(upsilon_(beat))=1/(upsilon_(1)-upsilon_(2))` |
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| 269. |
Define intensity of sound and loudness of sound. |
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Answer» 1. The loudness of sound is defined as “the degree of sensation of sound produced in the ear or the perception of sound by the listener”. 2. The intensity of sound is defined as “the sound power transmitted per unit area taken normal to the propagation of the sound wave”. |
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| 270. |
Write down the factors affecting velocity of sound in gases. |
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Answer» (a) Effect of pressure (b) Effect of temperature (c) Effect of density (e) Effect of wind |
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| 271. |
A transverse sinusoidal wave moves along a string in the positive x-direction at a speed of `10cm//s`. The wavelength of ythe wave is `0.5m` and its amplitude is `10cm`. At a particular time `t`, the snap-shot of the wave is shown in figure. The velocity of point `P` when its displacement is `5cm` is - A. (a) `sqrt(3)/(50)hat(J)m//s`B. (b) `-sqrt(3)/(50)hat(J)m//s`C. ( c ) `sqrt(3)/(50)hat(i)m//s`D. (d) `-sqrt(3)/(50)hat(i)m//s` |
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Answer» Correct Answer - A (a) Since the wave is sinusoidal moving in positive x-axis the point will move parallel to y-axis therefore options ( c ) and (d) are ruled out. As the wave moves forward in positive X-diretion, the point should move upwards i.e. in the positive Y-direction. therefore correct option is a. |
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| 272. |
What is the time period of a wave having angular frequency `(omega)` equal to `0.5s^(-1)`?A. 0.2 sB. 5 sC. 0.5 sD. 1.256 s |
| Answer» Correct Answer - D | |
| 273. |
Velocity of transverse waves in strings is given by the formula `V=sqrt((T)/(mu))`, where and `mu` are respectivelyA. Time period, coefficient of frictionB. tension, massC. tension, mass per unit lengthD. Time period, mass of per unit length |
| Answer» Correct Answer - C | |
| 274. |
With the increase in humidity, the velocity of sound in airA. increasesB. decreasesC. first increases and then decreasesD. becomes infinite |
| Answer» Correct Answer - A | |
| 275. |
A string of length 105 cm produces fundamental frequency of 142 Hz. How much should its length be reduced to produce a fundamental frequency of 213 Hz. |
| Answer» Correct Answer - 70 cm | |
| 276. |
Two ropes of length l and l/2 and mass per unit length `mu and mu//4` respectively are joined at B and hanged vertically with a heavy mass at its end C. A pulse is generated simultaneously at both ends A and C which travels along the ropes. Find the distance from the top at which pulses will cross each other. |
| Answer» Correct Answer - `(5l)/(8)` | |
| 277. |
A string with tension T and mass per unit length `mu` is clamped down at x=0 and at x=L. at t=0, the string is at rest and displaced in the y-direction `y(x,0)=2"sin"(2pix)/(L)+2"sin"(pix)/(L)` Q. What is the total energy at t=0?A. `(25Tpi^(2))/(4L)`B. `(25Tpi^(2))/(8L)`C. `(25Tpi^(2))/(2L)`D. `(25Tpi^(2))/(16L)` |
| Answer» Correct Answer - A | |
| 278. |
At particular instant a source of sound of frequency 1000 Hz is at (2m,1m) and an observer is at (5m,5m). The velocity of source and observer are `30(hati+hatj)m//s and 15(hati+sqrt(3)hatj)m//s` respectively at this instant. The velocity of sound in air is 330 m/s. find the frequency and wavelength of sound received by the observer. |
| Answer» Correct Answer - 1042 Hz, 29cm | |
| 279. |
A string with tension T and mass per unit length `mu` is clamped down at x=0 and at x=L. at t=0, the string is at rest and displaced in the y-direction `y(x,0)=2"sin"(2pix)/(L)+2"sin"(pix)/(L)` Q. At what time t will the string for the first time have exactly the same shape as it did at time t=0?A. `(L)/(2v)`B. `(L)/(v)`C. `(2L)/(v)`D. `(3L)/(v)` |
| Answer» Correct Answer - C | |
| 280. |
A narrow sound pulse (for example, a short pip by a whistle) is sent across a medium. (a) Does the pulse have a definite (i) frequency, (ii) wavelength, (iii) speed of propagation? (b) If the pulse rate is 1 after every 20 s, (that is the whistle is blown for a split of second after every 20 s), is the requency of the note produced by the whistle equal to 1/20 or 0.05 Hz? |
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Answer» (i)No (ii)No (iii)Yes No Explanation: The narrow sound pulse does not have a fixed wavelength or frequency. However, the speed of the sound pulse remains the same, which is equal to the speed of sound in that medium. The short pip produced after every 20 s does not mean that the frequency of the whistle is or 0.05 Hz. It means that 0.05 Hz is the frequency of the repetition of the pip of the whistle. |
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| 281. |
Class 11 Physics MCQ Questions of Waves with Answers? |
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Answer» The Class 11 Physics MCQ Questions of Wave with detailed solutions had been installation in keeping with the maximum current Syllabus, NCERT Books, and exam pattern advocated in Class 11 via way of means of CBSE. Students can start practice with MCQ Questions for class 11 Physics Wave with Answers for Board Exams. We have lists here top multiple-choice questions and detailed solutions on waves in physics. These MCQ Questions overall help in numerous examinations like physics and Competitive exams for engineering. Professionals, Teachers, Students check your knowledge with the assist of MCQ Questions for class 11. Practice MCQ Questions for class 11 Physics Chapter-Wise 1. A resonance air column of length 40 cm resonates with a tuning fork of frequency 450 Hz. Ignoring end correction, the velocity of sound in air will be (a) 720 m/s 2. With the increase in temperature, the frequency of the sound from an organ pipe (a) Decreases 3. Loudness of a note of sound is (a) Directly proportional to amplitude of the wave 4. To demonstrate the phenomenon of beats we need (a)Two sources which emit radiation of nearly the same frequency 5. Energy is not carried by (a) Longitudinal progressive waves 6. A resonating column of air contains (a) Stationary longitudinal waves 7. When a compression is incident on rigid wall it is reflected as (a) Compression with a phase change of p 8. When a sound wave goes from one medium to another, the quantity that remains unchanged is (a) frequency 9. Sound travels in rocks in the form of (a) both longitudinal and transverse elastic waves 10. The property of a medium necessary for wave propagation is (a) All of the above 11. The ratio of the speed of a body to the speed of sound is called (a) Mach number 12. Sound waves transfer (a) both energy and momentum 13. Statement 1: The base of Laplace correction was that exchange of heat between the region of compression and rarefraction in air is negligible Statement 2: Air is bad conductor of heat and velocity of sound in air is quite large (a) Statement-1 is false, Statement -2 is true 14. Which of the following changes at an antinode in a stationary wave? (a) Neither pressure nor density 15. What is the effect of humidity on sound waves when humidity increases? (a) Speed of sound waves is more 16. Closed organ pipe (closed at one end) is excited to support the third overtone. It is found that air in the pipe has (a) four nodes and four antinodes 17. If there are six loops for 1 m length in transverse mode of Melde’s experiment., the no. of loops in longitudinal mode under otherwise identical conditions would be (a) 3 18. The Doppler effect is applicable for (a) Light waves only 19. A man sitting in a moving train hears the whistle of the engine. The frequency of the whistle is 600 Hz: (a) the apparent frequency as heard by him is smaller than 600 Hz 20. If source and observer both are relatively at rest and if speed of sound is increased then frequency heard by observer will : (a) Increases 21. A source emits a sound of frequency of 400 Hz, but the listener hears it to be 390 Hz. Then (a) The listener is moving towards the source 22. Quality of a musical note depends on : (a) Harmonics present 23. Of the following the one which emits the sound of a higher pitch is : (a) Mosquito 24. Two waves having sinusoidal waveforms have different wavelengths and different amplitudes. They will be having : (a) Same pitch and different intensity 25. In a stationary wave along a string, the strain is : (a) zero at the antinodes Answer: 1. Answer: (a) 720 m/s Explanation: Here : Length of column = 40cm =0.4m Frequency of tuning fork = 450Hz Using the formula n= v/4l or v =450 × 4 × 0.4v = 720m/s 2. Answer: (b) Increases Explanation: Frequency ∝ v/L. Now v and L both increase with temperature but increase of v is much more than the increase of L which is negligible . Thus frequency increases with temperature. 3. Answer: (a) Directly proportional to amplitude of the wave Explanation: The loudness of a sound wave is determined from its amplitude. While loudness is only associated with sound waves, all types of waves have an amplitude. Waves on a calm ocean may be less than 1 foot high. 4. Answer: (a)Two sources which emit radiation of nearly the same frequency Explanation: To demonstrate the phenomena of interference, we require two sources which emit radiation of the same frequency and have a definite phase relationship. 5. Answer: (d) Stationary wave Explanation: The stationary or standing wave is a superposition of two waves of equal amplitude and frequency moving in opposite direction to each other and so there is no movement of the particles of the medium. That’s why there is no transfer of energy in the case of standing waves. 6. Answer: (a) Stationary longitudinal waves Explanation: In a resonating air column, longitudinal standing waves are formed. A standing wave is formed when two waves of same amplitude and same frequency, moving with same speed but opposite in direction interfere. A standing wave does not propagate in any direction and it oscillates at one place. 7. Answer: (a) Compression with a phase change of p Explanation: Therefore, a compression which is travelling towards the wall is reflected as a compression in the direction opposite to the wall and a rarefaction incident on the wall is reflected as a rarefaction. 8. Answer: (a) frequency Explanation: The physical quantity that remain unchanged when a sound wave goes from one medium to another is frequency. 9. Answer: (a) both longitudinal and transverse elastic waves Explanation: Sound travels in rocks in the form of both longitudinal and transverse waves, but in air, sound travels only in the form of longitudinal waves'. 10. Answer: (a) All of the above Explanation: The properties of a medium necessary for wave propagation are its elasticity, low resistance and inertia. 11. Answer: (a) Mach number Explanation: Mach number is defined as the ratio of speed of a body to the speed of sound in air. 12. Answer: (a) both energy and momentum Explanation: Sound waves transfer both energy and momentum. 13. Answer: (c) Statement-1 is true, Statement-2 is true; Statement-2 is not a correct explanation for statement-1 Explanation: Laplace corrected Sir Newton's formula for velocity of sound in a gas , by saying that ,when sound wave propagates in a gas , change in pressure and volume in compressions and rarefactions is not an isothermal change but an adiabatic change , and we know that in an adiabatic change there is no exchange of heat between gas and surrounding ( air) , therefore statement -1 is true . On the other hand velocity of sound in a gas (or air) is not related with the conductivity of gas as by the relation given by Laplace . 14. Answer: (a) Neither pressure nor density Explanation: Pressure and density do not change at an anti-node in a stationary wave. 15. Answer: (a) Speed of sound waves is more Explanation: Humidity affects the sound waves. Since Humidity contains more water vapour the medium becomes denser. Consequently the sound would travel faster, means frequency increases. 16. Answer: (b) four nodes and three antinodes Explanation: It is known that when closed pipe vibrates in fundamental mode, there are one node and one antinode. When it vibrates in first overtone, there are two nodes and two antinodes. When it vibrates in second overtone, there are three nodes and three antinodes. When it vibrates in third overtone, there are four nodes and four antinodes. 17. Answer: (a) 3 Explanation: One cycle of up and down vibration for transverse waves on the string is two cycles of string tension increase and decrease. The tension is maximum both at the loops’ maximum up position and again at maximum down position. Therefore, in longitudinal drive mode, since the string tension increases and decreases once per tuning fork vibration, it takes one tuning fork vibration to move the string loop to maximum up position and one to move it to maximum down position. This is two tuning fork vibrations for one up and down string vibration, so the tuning fork frequency is half the string frequency. Hence, the number of loops in longitudinal mode(tuning fork) is half of that of transverse mode(string). 18. Answer: (c) Both light and sound waves Explanation: The Doppler effect occurs when the motion of wave source and observer is relative. As we know light and sound, both are waves. Thus Dopler effect is applicable to both sound and light waves. 19. Answer: (c) the frequency as heard by him is 600 Hz Explanation: Since there is no no relative motion between the listener and source, hence actual frequency will be heard by listener. 20. Answer: (d) Will not change Explanation: The apparent change in the frequency of the source due to a relative motion between the source and observer is known as Doppler's effect. In the given case there is no relative motion between source and observer, since both are at rest, hence frequency of sound heard by the observer will remain unchanged. 21. Answer: (a) The listener is moving towards the source Explanation: Since apparent frequency is lesser than the actual frequency, hence the relative separation between source and listener should be increasing. 22. Answer: (a) Harmonics present Explanation: The quality of sound depends upon the number of harmonics present. Due to different number of harmonics present in two sounds, the shape of the resultant wave is also different. 23. Answer: (a) Mosquito Explanation: Pitch of mosquito is higher among all given options. 24. Answer: (c) Different quality and different intensity Explanation: The pitch depends upon the frequency of the source. As the two waves have different amplitude, therefore, they having different intensity. while quality depends on a number of harmonics/overtone produced and their relative intensity. Assuming that their frequencies are the same. 25. Answer: (d) maximum at the nodes Explanation: In a stationary wave strain is maximum at the node because two opposite forces act at the node. Click here to practice MCQ Questions for Waves class 11 |
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| 282. |
What are the parameters used to describe a progressive harmonic wave ? |
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Answer» Progressive wave equation is given y `= a sin ( omega t - kx) ` Where `omega = 2 pi v ( 2pi)/(T ) , k = ( 2pi)/( lambda) ` Parameters `:` (1) a = Amplitude (2) `lambda = ` Wavelength (3) T = Time period (4) v = Frequency (5) k = Propagation constant (6) `omega `= Angular frequency |
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| 283. |
Distinguish between longitudinal and transverse waves. |
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Answer» 1. The vibration of particles of the medium is along the direction of wave propagation in longitudinal waves, whereas in transverse waves, the vibration of particles of the medium is perpendicular to the direction of wave propagation. 2. The wave propagates by forming alternate compressions and rarefactions in longitudinal waves, whereas in transverse waves, the wave propagates by forming alternative crests and troughs. 3. Longitudinal waves travel through solids, gases, and liquids, whereas Transverse waves travel through solids and on 1 liquid surfaces. 4. Longitudinal waves cannot be polarised, whereas Transverse waves can be polarised. 5. Distance between two successive compressions or rarefactions is equal to the wavelength of the wave in longitudinal waves, whereas, in transverse waves, the distance between two successive crests or troughs is equal to the wavelength of the wave. |
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| 284. |
A set of 65 tuning forks are arranged In the Increasing order of frequencies such that each gives 3 beats per second with the previous one. Find the frequency of the first tuning fork If the frequency of the last tuning fork Is one Octave above the first one. |
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Answer» Let N be the frequency of the first tuning fork. As each tuning fork is giving 3 beats with the preceding one, and they are arranged in the ascending order of frequencies, Frequency of the second tuning fork = N + 3 Frequency of the third T.F. = N + 6 = N + 3 × 2 Frequency of the fourth T.F = N+9 = N + 3 × 3 Similarly Frequency of the 65th T.F. = N + (65-1 ) × 3 = N + 64 × 3 = N + 192 …….(1) But the frequency of the last tuning fork (65th) is one octave above that of the first one. ∴ Frequency of the 65th T.F.= 2N ………(2) From (1) and (2) 2N = N + 192 N = 192 ∴ Frequency of the first tuning fork = 192 Hz. |
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| 285. |
The followig figure shows a wave propagating in a string. The speed of point A, which is 3 cm above the mean position is `7sqrt(3)picm//s` at the moment shown. What is the speed of the wave in m/s? |
| Answer» Correct Answer - 7 | |
| 286. |
A string of mass `m` is fixed at both ends. The fundamental tone oscillations are excited with circular frequency `omega` and maximum displacement amplitude `a_(max)` . Find `:` `(a)` the maximum kinetic energy of the string, `(b)` the mean kinetic energy of the string averaged over one oscillation period. |
| Answer» `(pi^(2)t^(2)mA^(2))/(2)` | |
| 287. |
How does velocity of sound vary with pressure? |
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Answer» The velocity of sound is independent of pressure. |
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| 288. |
A 10 m long steel wire has mass 5 g. If the wire is under a tension of 80 N, the speed of transverse waves on the wire isA. `100ms^(-1)`B. `200ms^(-1)`C. `400ms^(-1)`D. `500ms^(-1)` |
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Answer» Correct Answer - C Here, Length, L = 10 m Mass, M=5 kg =`5xx10^(-3)` kg Tension, T=80 N Mass per unit length of the wire is `mu=M/L=(5xx10^(-3)kg)/(10m)=5xx10^(-4)kgm^(-1)` Speed of the transverse wave on the wire is `v=sqrt(T/mu)=sqrt((80 N)/(5xx10^(-4)kgm^(-1)))` `=4xx10^(2)ms^(-1)=400ms^(-1)` |
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| 289. |
A steel wire 100 cm long has a mass of 10 gm. If the wire is under a tension of 400 N, what is the speed of transverse waves in the wire? |
| Answer» Correct Answer - 200m/s | |
| 290. |
A mechanical wave has a velocity of 330 m/s. calculate its frequency if its wavelength is 130m. |
| Answer» Correct Answer - 2.54 Hz | |
| 291. |
The frequency of a mechanical wave is 256 Hz. Calculate its wavelength when its speed is 512m/s. |
| Answer» Correct Answer - 2m | |
| 292. |
What is a mechanical wave? |
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Answer» A wave which requires a medium for its propagation is called a mechanical wave. |
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| 293. |
A sonometer wire is under a tension of 10 N and the length between the bridges is 2m. A metre long wire of sonometer has mass of 1.0 gm. Deduce the speed of transverse wave and the frequency of 1st hormonic. |
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Answer» `v=100m//s` `v=25Hz` |
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| 294. |
Give an example of a transverse wave. |
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Answer» Light waves. |
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| 295. |
What is a transverse wave? |
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Answer» In transverse waves, particles of the medium are vibrating perpendicular to the direction of wave propagation. |
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| 296. |
Give an example of a two-dimensional wave. |
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Answer» Water waves. |
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| 297. |
Column-II lists some equations and arrangements of string. They are either corresponding to stationary wave or progressive wave match the entries of column-I with all possible entries in column-II |
| Answer» Correct Answer - A::B::C::D | |
| 298. |
Match the column |
| Answer» Correct Answer - A::B::C | |
| 299. |
Assertion : Sound level increases linearly with intensity of sound. Reason : If intensity of sound is doubled, sound level increases approximatel `3 dB` .A. Statement-1 is true, statement-2 is true, statement-2 is a correct explanation for statement-1B. Statement-1 is true, statement-2 is true, statement-2 is not a correct explanation for statement-1C. statement-1 is true, statement-2 is falseD. statement-1 is false, statement-2 is true |
| Answer» Correct Answer - D | |
| 300. |
What are the characteristics of progressive wave? |
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Answer» 1. A progressive wave is formed due to continuous vibration of the particles of the medium. 2. The wave travels with a certain velocity. 3. There is a flow of energy in the direction of the wave. 4. No particles in the medium are at rest. 5. The amplitude of all the particles is the same. 6. Phase changes continuously from par¬ticle to particle. |
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