Team Quanta gladly presents all possible short questions of BS Physics book Waves and Oscillation Chapter#02: Wave in Physical Media.
Q.1 A wave transmits energy. Does it transfer linear momentum? Can it transfer angular momentum?
Answer: Yes, waves transfer energy and linear momentum. A wave can also transfer angular momentum by causing a body to rotate when place in its path.
Q.2 Can a wave motion be generated in which particles of the medium vibrate with angular simple harmonic motion?
Answer: If two identical harmonic traveling waves having the same phase and traveling in mutually perpendicular directions are made to combine in the medium, angular simple harmonic motion is produced.
Q.3 When two waves interfere, does one alter the progress of the other? Explain.
Answer: No, the waves continue their individual motion without disturbing each other, each wave acting on the medium independently.
Q.4 Can one produce on a string a wave form that has a discontinuity in shape at a point, that is, one having a sharp corner?
Answer: Yes, it is possible by sending several harmonic waves on the string with different set of frequencies.
Q.5 What are progressive or travelling waves?
Answer: Progressive or travelling waves transfer energy from one place to another place without transfer the matter in the form one molecule transfer energy with the help of molecules by oscillation process for example light coming from the seen.
Q.6 How could you prove experimentally that energy can be transported by a wave?
Answer: A body placed in the path of a wave can be set into motion thus proving that the waves carry energy.
Q.7 Define the principle of superposition.
Answer: The superposition principle states that, for all linear systems, the net response caused by two or more stimuli is the sum of the responses that would have been caused by all each stimulus individually.
Q.8 Energy can be transferred by particle as well as waves. How can we distinguish between these methods of energy transfer experimentally?
Answer: The energy transfer by waves is gradual and takes some time for complete transfer. The transfer of energy by particles is instantaneous.
Q.9 Differentiate between group velocity and phase velocity.
Answer: The group velocity is the velocity of the wave with lower frequency, but the phase velocity is the velocity of the wave with higher frequency. Phase velocity is defined for both, the single waves and superimposed waves. The group velocity is defined only to the superimposed waves.
Q.10 The following functions, in which A is a constant, are of the form : $\mathbf{A(X\pm Vt): Y=A\left(X-Vt\right);Y=A\left(X+Vt\right);Y=A\sqrt{\left(X-Vt\right)}\ ,Y=A\ \ln{\left(X-Vt\right)}}$ . Explain why these functions are not useful in wave motion.
Answer: In a wave motion equation Y is a parameter that is periodic and repeats itself after regular time intervals. In all these equations, Y is a periodic function of time t. hence these equations can be used for representing a wave.
Q.11 A passing motor boat crates a wake that causes waves to wash ashore. As time goes on, the period of the arriving waves grows shorter and shorter. Why?
Answer: The reflection back of the ashore waves with the incident waves causes the frequency of the wave to increase as a result of which the time period of the waves decreases gradually.
Q.12 When waves interfere, is there a less of energy?
Answer: Although at the position of constructive interference one notices a creation of energy while at position of destructive interference, it appears a loss of energy but there is violation of law of conservation of energy in interference of waves. Energy simple redistributes itself form positions of destructive interference.
Q.13 If two waves differ in amplitude and travel in opposite directions through a medium, will they produce stationary waves? Is energy transported? Are there any nodes?
Answer: No, the two waves will not produce standing wave pattern. There are no nodes and the energy is transferred.
Q.14 What is longitudinal wave? Does light wave is longitudinal.
Answer: The mechanical waves in which particle of the medium vibrate along the direction of the propagation of the waves are called longitudinal waves. Not, light waves are transverse waves.
