Chpt 19 Wave PHYSICS

Question 1

1. Which of the following best describes a wave?A. Transport of energy through spaceB. Propagation of mass and energyC. Transfer of mass between pointsD. Vibration of particles in a single point

Answer 1

Answer: AExplanation: Waves are disturbances that result in the transfer of energy not mass across distances. Examples include sound waves and electromagnetic waves.

Question 2

2. What is the characteristic of a wavefront?A. It is the line connecting crests and troughsB. It is the surface where all points have the same phaseC. It connects points of minimum amplitudeD. It is the path of the energy flow

Answer 2

Answer: BExplanation: A wavefront represents the surface over which particles are in the same phase of vibration meaning they oscillate together.

Question 3

3. What type of wave is a sound wave?A. Transverse waveB. Longitudinal waveC. Spherical waveD. Surface wave

Answer 3

Answer: BExplanation: Sound waves are longitudinal waves where particles oscillate in the same direction as the wave’s propagation.

Question 4

4. The motion of particles in transverse waves is characterized by vibrations that areA. Parallel to the wave directionB. Perpendicular to the wave directionC. Circular in natureD. Random

Answer 4

Answer: BExplanation: In transverse waves particle displacement is perpendicular to the direction of the wave’s travel.

Question 5

5. Which of the following is a type of transverse wave?A. SoundB. Earthquake wavesC. LightD. Tidal waves

Answer 5

Answer: C

Question 6

Explanation: Light is an electromagnetic wave classified as transverse due to the perpendicular oscillation of electric and magnetic fields.

Question 7

6. Electromagnetic waves consist of oscillating fields in which orientation?A. Both fields are parallel to each otherB. Both fields are at right angles to each otherC. Only one field oscillatesD. Both fields are parallel to the wavefront

Answer 7

Answer: BExplanation: Electromagnetic waves have electric and magnetic fields oscillating perpendicularly to each other and to the direction of wave travel.

Question 8

7. What determines the velocity of a wave in a medium?A. The wavelength of the waveB. The frequency and medium propertiesC. The medium temperature onlyD. The amplitude of the wave

Answer 8

Answer: BExplanation: The velocity of a wave depends on the medium’s properties and sometimes the frequency of the wave as seen with sound waves.

Question 9

8. A wave with a frequency of 500 Hz has a period ofA. 0.002 sB. 0.005 sC. 2 sD. 5 s

Answer 9

Answer: BExplanation: Period thus seconds.

Question 10

9. Which type of wave is characterized by compressions and rarefactions?A. Transverse waveB. Electromagnetic waveC. Longitudinal waveD. Tidal wave

Answer 10

Answer: CExplanation: Longitudinal waves have compressions and rarefactions where particles move parallel to the wave direction.

Question 11

10. In a standing wave what are nodes?A. Points of maximum displacementB. Points of zero or minimum displacementC. Points of random movementD. Points where the wave velocity is highest

Answer 11

Answer: BExplanation: Nodes are points along a standing wave where displacement remains zero.

Question 12

11. In the context of waves amplitude refers toA. The distance between two nodesB. The maximum displacement from a mean positionC. The frequency of the waveD. The time it takes to complete one cycle

Answer 12

Answer: BExplanation: Amplitude is the maximum displacement of particles from their equilibrium position in a wave.

Question 13

12. How are mechanical waves primarily different from electromagnetic waves?A. They require a mediuB. They travel fasterC. They have no energy transferD. They exist only in solids

Answer 13

Answer: AExplanation: Mechanical waves like sound need a medium unlike electromagnetic waves that can travel in a vacuum.

Question 14

13. The distance between successive crests in a wave is theA. WavelengthB. AmplitudeC. FrequencyD. Period

Answer 14

Answer: AExplanation: Wavelength is the distance between two consecutive crests or troughs.

Question 15

14. What does the phase of a wave describe?A. Speed of the waveB. Direction of wave travelC. Position within a wave cycleD. Amplitude of vibration

Answer 15

Answer: CExplanation: Phase indicates the position of a point in the cycle of the wave often measured in radians.

Question 16

15. If a wave travels 8 meters in 0.04 seconds its speed isA. 400 m/sB. 200 m/sC. 100 m/sD. 50 m/s

Answer 16

Answer: BExplanation: Speed m/s.

Question 17

16. How does a transverse wave differ from a longitudinal wave?

Answer 17

Answer: In transverse waves particle movement is perpendicular to wave direction while in longitudinal waves particles move parallel to wave direction.

Question 18

17. Define wavefront

Answer 18

Answer: A wavefront is the surface over which particles of a medium have the same phase of vibration like crests in water waves.

Question 19

18. What is meant by the amplitude of a wave?

Answer 19

Answer: Amplitude is the maximum displacement from the mean position of particles in a wave indicating the wave’s energy level.

Question 20

19. Describe one characteristic that distinguishes a standing wave from a traveling wave

Answer 20

Answer: Standing waves have nodes (points of no displacement) and antinodes (points of maximum displacement) unlike traveling waves where energy continuously propagates.

Question 21

20. Explain how frequency and period are related

Answer 21

Answer: Frequency is the number of cycles per second while the period is the time for one cycle; they are inversely related.

Question 22

21. What happens to wave speed when it enters a denser medium?A. It increasesB. It decreasesC. It stays the sameD. It becomes zero

Answer 22

Answer: BExplanation: Waves typically slow down in denser media due to increased resistance to movement.

Question 23

22. The distance moved by a wave in one second is known asA. FrequencyB. WavelengthC. VelocityD. Amplitude

Answer 23

Answer: CExplanation: Wave velocity represents how fast a wave travels calculated as distance per unit time.

Question 24

23. If two waves of the same frequency have different phases they are said toA. Have different amplitudesB. Be out of phaseC. Be in phaseD. Have different wavelengths

Answer 24

Answer: BExplanation: Different phases imply a phase difference causing constructive or destructive interference.

Question 25

24. The frequency of a wave is measured inA. MetersB. HertzC. NewtonsD. Joules

Answer 25

Answer: BExplanation: Frequency is measured in Hertz (Hz) which represents cycles per second.

Question 26

25. Which property of sound waves makes them audible?A. VelocityB. FrequencyC. WavelengthD. Amplitude

Answer 26

Answer: BExplanation: Audible frequencies fall within the human hearing range typically between 20 Hz and 20 kHz.

Question 27

26. Which of these waves can travel in a vacuum? A. Sound wavesB. Water wavesC. Electromagnetic wavesD. Seismic waves

Answer 27

Answer: CExplanation: Electromagnetic waves such as light

Question 28

27. In a wave the time taken for one complete oscillation is known asA. FrequencyB. PeriodC. WavelengthD. Velocity

Answer 28

Answer: BExplanation: The period is the time for one full cycle inversely related to frequency.

Question 29

28. If the amplitude of a sound wave increases what happens to its loudness?A. It decreasesB. It increasesC. It remains constantD. It becomes inaudible

Answer 29

Answer: BExplanation: Loudness is directly related to amplitude greater amplitude results in a louder sound.

Question 30

29. What causes constructive interference in waves?A. Two waves of different frequenciesB. Two waves in opposite directionsC. Two waves of the same amplitude meeting out of phaseD. Two waves meeting in phase

Answer 30

Answer: DExplanation: Constructive interference occurs when waves meet in phase combining to produce a wave with greater amplitude.

Question 31

30. Which statement is true for light waves but not sound waves?A. They require a mediumB. They are longitudinalC. They can be polarizedD. They travel faster in denser medis

Answer 31

Answer: CExplanation: Light waves can be polarized as they are transverse electromagnetic waves while sound waves which are longitudinal cannot be polarized.

Question 32

1. Explain the difference between transverse and longitudinal waves providing examples of each.

Answer 32

Explanation: Transverse waves involve oscillations perpendicular to the direction of propagation (e.g. light and water waves) while longitudinal waves have oscillations parallel to the direction of propagation (e.g. sound waves).

Question 33

2. Describe the concept of wavefront and its significance in understanding wave propagation.

Answer 33

Explanation: A wavefront is the surface over which all points are in the same phase of vibration. Understanding wavefronts helps in visualizing wave propagation interference and reflection patterns.

Question 34

3. How does the frequency of a wave affect its energy and speed in a given medium?

Answer 34

Explanation: In general higher frequency waves have more energy. However in a specific medium wave speed is usually constant and depends on the properties of the medium rather than frequency.

Question 35

4. What role does amplitude play in the perception of sound waves and how does it differ from frequency

Answer 35

Explanation: Amplitude influences the loudness of sound while frequency affects pitch. Higher amplitude results in louder sounds whereas higher frequency produces higher-pitched sounds.

Question 36

5. Describe the process of wave interference and differentiate between constructive and destructive interference.

Answer 36

Explanation: Interference occurs when two waves meet. Constructive interference happens when waves meet in phase amplifying the resultant wave while destructive interference occurs when waves meet out of phase reducing or canceling out the resultant wave.

Question 37

Question 1: What does the angular frequency (ω) represent in wave motiona) The number of cycles completed per secondb) The rate of change of displacementc) The angle made with timed) The distance covered in one cycle

Answer 37

Answer: c) The angle made with timeExplanation: Angular frequency is the measure of the rate at which an object moves through an angle in a given amount of time often in radians per second. This is represented by the symbol ω and is an essential aspect of circular and oscillatory motion.

Question 38

Question 2: In the context of waves what does the term ‘amplitude’ refer to?a) The distance between two consecutive peaksb) The time taken for one full cyclec) The maximum displacement from the mean positiond) The frequency of the wave

Answer 38

Answer: c) The maximum displacement from the mean positionExplanation: Amplitude is the maximum extent of vibration or oscillation measured from the mean or equilibrium position. It indicates the energy level of the wave.

Question 39

Question 3: What is the phase difference between two points in a wave separated by half a wavelength?a) π radiansb) 2π radiansc) π/2 radiansd) 0 radians

Answer 39

Answer: a) π radiansExplanation: A separation of half a wavelength corresponds to a phase difference of π radians. This means that the points are 180 degrees out of phase.

Question 40

Question 4: Which of these properties do all types of waves exhibit?a) Reflection refraction diffractionb) Amplitude frequency speedc) Interference beats Doppler Effectd) All of the above

Answer 40

Answer: d) All of the aboveExplanation: Waves exhibit several properties including reflection refraction diffraction interference beats and the Doppler Effect. These properties can be observed across different wave types such as sound and light waves.

Question 41

Question 5: The equation represents:a) The displacement of a standing waveb) The displacement of a progressive wavec) The energy of the waved) The wavelength of the wave

Answer 41

Answer: b) The displacement of a progressive waveExplanation: This equation describes a progressive (or traveling) wave where is the amplitude is the angular frequency is the time is the wave number and is the position.

Question 42

Question 6: If the frequency of a wave is 10 Hz what is the angular frequency (ω)?a) 5 rad/sb) 20 rad/sc) 62.8 rad/sd) 31.4 rad/s

Answer 42

Answer: d) 62.8 rad/sExplanation: Angular frequency ω is given by. Substituting gives.

Question 43

Question 7: What is the wavelength of a wave if its speed is 17 m/s and its frequency is 1 Hz?a) 17 mb) 8.5 mc) 34 md) 1 m

Answer 43

Answer: a) 17 mExplanation: Wavelength is calculated by the formula. With and we get.

Question 44

Question 8: A wave is reflected at a boundary with its phase inverted. Which type of boundary is this?a) Open boundaryb) Fixed boundaryc) Free boundaryd) Moving boundary

Answer 44

Answer: b) Fixed boundaryExplanation: When a wave is reflected at a fixed boundary its phase is inverted meaning the reflected wave is the mirror image of the incident wave with an opposite phase.

Question 45

Question 9: The displacement equation has an amplitude of:a) 20b) 0.1c) 10d) 1

Answer 45

Answer: b) 0.1Explanation: The amplitude in a wave equation is represented by which is 0.1 in this case.

Question 46

Question 10: Which of the following describes the distance between two nodes in a stationary wave?a) Half a wavelengthb) One wavelengthc) A quarter wavelengthd) Double the wavelength

Answer 46

Answer: a) Half a wavelengthExplanation: In a stationary wave the distance between two consecutive nodes (or antinodes) is half of the wavelength.

Question 47

Question 11: What happens to the speed of a wave if the frequency is doubled while the wavelength remains constant?a) It doublesb) It halvesc) It quadruplesd) It remains constant

Answer 47

Answer: a) It doublesExplanation: Wave speed. If is doubled and remains the same will also double.

Question 48

Question 12: The frequency of a wave is 20 Hz. What is its period?a) 0.05 sb) 5 sc) 0.2 sd) 2 s

Answer 48

Answer: a) 0.05 sExplanation: Period. So.

Question 49

Question 13: Which phenomenon explains the production of echoes?a) Diffractionb) Reflectionc) Refractiond) Interference

Answer 49

Answer: b) ReflectionExplanation: Echoes are produced when sound waves are reflected off surfaces and return to the listener.

Question 50

Question 14: In a wave the nodes have:a) Maximum displacementb) Zero displacementc) Half the maximum displacementd) Twice the maximum displacement

Answer 50

Answer: b) Zero displacementExplanation: Nodes are points in a stationary wave where the amplitude is zero due to destructive interference.

Question 51

Question 15: The maximum phase difference between two points separated by a full wavelength is:a) π radiansb) 2π radiansc) π/2 radiansd) 0 radians

Answer 51

Answer: b) 2π radiansExplanation: A full wavelength corresponds to a phase difference of 2π radians.

Question 52

Question 16: The speed of sound in air is approximately:a) 100 m/sb) 343 m/sc) 1500 m/sd) 299792 m/s

Answer 52

Answer: b) 343 m/sExplanation: In air the speed of sound is around 343 m/s under standard conditions.

Question 53

Question 17: Explain the Doppler Effect and provide an example of its application in real life.

Answer 53

Answer: The Doppler Effect is the change in frequency or wavelength of a wave in relation to an observer moving relative to the wave source. An example is the change in pitch of a siren as an ambulance passes by.

Question 54

Question 18: Describe the difference between transverse and longitudinal waves.

Answer 54

Answer: Transverse waves oscillate perpendicular to the direction of propagation whereas longitudinal waves oscillate parallel to it. Sound is a longitudinal wave while light is a transverse wave.

Question 55

Question 19: What is interference in the context of waves?

Answer 55

Answer: Interference is the phenomenon that occurs when two waves meet resulting in a new wave pattern. This can be constructive (amplitude increases) or destructive (amplitude decreases).

Question 56

Question 20: Explain how standing waves are formed on a string fixed at both ends.

Answer 56

Answer: Standing waves form when two waves of the same frequency and amplitude travel in opposite directions along a medium creating nodes and antinodes due to interference.

Question 57

Question 21: How does the concept of phase difference help in analyzing wave patterns?

Answer 57

Answer: Phase difference helps determine the relative position and motion of two points on a wave useful in understanding wave interference and resonance.

Question 58

Question 22: Describe the effect of amplitude on the energy of a wave.

Answer 58

Answer: The energy of a wave is proportional to the square of its amplitude. Higher amplitude means more energy as seen in louder sounds or brighter light waves.