FBQ1: Linear simple harmonic motion (SHM) along a straight line inclined equally to the straight lines of motion of two mutually perpendicular SHM of same____________ amplitude and phase which are superimposed on one another Answer: *frequency* FBQ2: The velocity at the equilibrium position in a given SHM is ____________ Answer: *maximum* FBQ3: When a wave travels through a medium, the resistance to wave motion in a medium is called ____________. Answer: *Impedance* FBQ4: In a____________, the magnitude of restoring force is linearly proportional to the displacement Answer: *spring-mass system* FBQ5: What is the frequency of oscillation of a particle whose period of oscillation is 0.08 seconds? Answer: *12.5Hz* FBQ6: The restoring force is always directed towards the____________, of an oscillating body. Answer: *equilibrium position* FBQ7: ____________, is a type of periodic motion where the restoring force is proportional to the displacement. Answer: *Harmonic vibration* FBQ8: In the case of simple harmonic motion (SHM), if the particle is at the mean position, then the particle is in____________, Answer: *Stable equilibrium* FBQ9: The number of vibrations per second executed by an oscillator in SHM is called ____________, Answer: *frequency* FBQ10: The k/m in the above equation is replaced by ω02 angular frequency of the oscillatory motion, because they have____________, Answer: *same unit* FBQ11: When a system is said to be heavily damped, the motion of the system is said to be ____________, Answer: *Dead beat* FBQ12: The time taken for an oscillating particle to complete one vibration is called ____________, Answer: *Period* FBQ13: xt=mcos(w0t+φ), the amplitude of this equation is ____________, Answer: *m* FBQ14: ____________, is defined as Maximum displacement of an oscillating body Answer: *Amplitude * FBQ15: Calculate the characteristic impedance offered by a thin wire of steel stretched by a force of 80 N weighing 2g per metre. Answer: *0.4 N/ms* FBQ16: The shape of the curve of two orthonormal vibrations with exactly the same frequency depends on the _____between component vibrations Answer: *Phase difference* FBQ17: What sound does our vocal cord create inside the throat when we talk? Answer: *Vibration* FBQ18: When a progressive wave reaches the boundary of a finite medium or an interface between two media, waves undergo_____ or/and _____. Answer: *Reflection, refraction* FBQ19: ____________ is the minimum displacement of wave. Answer: *Trough* FBQ20: At an instant of time during the oscillations of an LC circuit when the current is at its maximum value. At this instant, voltage across the ____________ is zero. Answer: *capacitor* FBQ21: Waves set up by a single, isolated disturbance are called ____________ Answer: *Pulses* FBQ22: The simplest type of a periodic wave is a ____________ wave. Answer: *harmonic* FBQ23: _____ are waves that occur at the boundary Answer: *Rayleigh waves* FBQ24: The displacement of a particle executing simple harmonic motion is given by, x= 0.25cos(4πt+0.078) in meter. The amplitude is____________ Answer: *0.25* FBQ25: When the two individual rectangular vibrations are of slightly different frequencies, the resulting motion is more complex. True or False Answer: *True* FBQ26: The ____________ of electromagnetic waves govern the working of a radar for detection of aircrafts. Answer: *Reflection* FBQ27: When a wave moves from a lighter to a denser medium, its velocity ____________ Answer: *Decreases* FBQ28: The ____________ conditions are the conditions which must be satisfied at the interface where the two media meet Answer: *boundary* FBQ29: When Z2>Z1, the second string (medium) is denser, R12 is still ____________, implying a phase change of π on reflection. Answer: *Negative* FBQ30: When resistance to motion is very strong, the system is said to be heavily ___ Answer: *damped* FBQ31: If the source of a wave is so far from away from an aperture that the wave front generating the diffraction pattern is regarded as plane wave front, we have _____ diffraction Answer: *Fraunhofer* FBQ32: The waves produced by a motor boat sailing in water are____________ Answer: *Transverse waves* FBQ33: ____________ is the superposition of many waves of same amplitude and frequency, but differing slightly in phase. Answer: *Diffraction* FBQ34: Oscillations become damped due to ___ force Answer: *Frictional* FBQ35: The frequency of an LC oscillator is Inversely proportional to the ___ of L or C Answer: *square root* Multiple Choice Questions (MCQs): MCQ1: For a simple harmonic oscillator, Answer: the total energy is proportional to the square of the amplitude MCQ2: Which of the following is not a property of a longitudinal wave? Answer: Polarisation MCQ3: If the amplitude of a simple harmonic oscillator is tripled, by what factor is the energy changed? Answer: 3 MCQ4: A pendulum suspended from the roof of a train has a period T (When the train is at rest). When the train is accelerating with a uniform acceleration ‘a’, the time period of the pendulum will ________. Answer: Remain unaffected MCQ5: In simple harmonic motion, velocity at equilibrium position is ________. Answer: Maximum MCQ6: Over-damping results to ________. Answer: arrhythmic return to equilibrium MCQ7: In simple harmonic motion (SHM), the particle is: Answer: Alternately accelerated and retarded MCQ8: A damped system is characterised by all of the following except ________. Answer: relaxation time MCQ9: The total energy of a particle executing SHM is proportional to ________. Answer: displacement from equilibrium positionfrequency of oscillation MCQ10: A 2.00 kg block attached to a spring is pulled a distance of 5.00 cm from the equilibrium position and released at t = 0. If the block execute SHM with angular frequency of 9.90 rad/s, find the force constant of the spring and the frequency of oscillation of the block. Answer: 49 N/m; 2.0 Hz MCQ11: Which of the following represent stokes law? Answer: 6πrv MCQ12: A cart of mass 0.500 kg connected to a light spring for which the force constant is 20.0 N/m oscillates on a frictionless, horizontal air track. Calculate the maximum speed of the cart if the amplitude of the motion is 3.00 cm. Answer: 3.0 m/s MCQ13: A vibration of a pendulum in a viscous medium such as thick oil is an example of ________. Answer: Damped system MCQ14: For a simple harmonic oscillator, the number of vibrations executed per second is called _______________ Answer: Period MCQ15: The intensity of a wave is the measure of its ________. Answer: power across a unit area perpendicular to the direction of motion MCQ16: A student tunes a guitar by comparing the sound of the string with that of a standard tuning fork. He notices a beat frequency of 5 Hz when both sounds are superposed. He tightens the guitar string and finds the beat frequency rises to 8 Hz. What should he do to match the frequency of the string to that of the tuning fork? Answer: He must tighten the guitar string MCQ17: A note of frequency 1200 vibrations/s has an intensity of 2.0µW/m2. What is the amplitude of the air vibrations caused by this sound? Answer: 2.28×10-4 m MCQ18: When the motion of particles of the medium is along the direction in which wave propagates, it is called a ____. Answer: Barrier Wave MCQ19: Oscillations become damped due to ________. Answer: Frictional force MCQ20: The time period of a pendulum on Earth is 1.0 s. What would be the period of a pendulum of the same length on a planet with half the density but twice the radius of Earth? Answer: 1.0s MCQ21: Two sound waves have intensities 0.4 and 10W/m2, respectively. How many decibels is one louder than the other? Answer: 14 Db MCQ22: A simple pendulum has a period of 2 s and an amplitude of 50. After 20 complete oscillations, its amplitude is reduced to 40. Find the damping constant and the time constant. Answer: 175.5 s-1 MCQ23: The quality factor of a sonometer wire is 4,000. The wire vibrates at a frequency of 300 Hz. Find the time in which the amplitude decreases to half of its original value. Answer: 2.94s MCQ24: What is the ratio of the wavelength to the period of a wave? Answer: displacement MCQ25: A block of mass m is first allowed to hang from a spring in static equilibrium. It stretches the spring a distance L beyond the spring’s unstressed length. If the block and spring system is set into oscillation, how will its period compare with the period of a simple pendulum of length L and mass m? Answer: Less than that of simple pendulum MCQ26: A box of mass 0.2 kg is attached to one end of a spring whose other end is fixed to a rigid support. When a mass of 0.8 kg is placed inside the box, the system performs 4 oscillations per second and the amplitude falls from 2 cm to 1 cm in 30 sec. Calculate the quality factor. Answer: 100 MCQ27: The quality factor of a tuning fork of frequency 512Hz is 6*10^4. Calculate the time in which its energy is reduced to e-1 of its energy in the absence of damping. Answer: 17.5s MCQ28: The quality factor of a tuning fork of frequency 512Hz is 6*10^4. How many oscillations will the tuning fork make in this time? Answer: 92.5*102 MCQ29: As amplitude of resonant vibrations decreases, degree of damping ______. Answer: Decreases MCQ30: An electric bell has a frequency 100Hz. If its time constant is 2s, determine the Q factor for the bell. Answer: 2256 MCQ31: The dot or scalar product of a force and a displacement vectors defines ______. Answer: Work MCQ32: In cars, springs are damped by ______. Answer: Engines MCQ33: The distance between successive particles vibrating in phase is known as ____. Answer: Frequency MCQ34: What is the ratio of the lengths of two pendulums if the ratio of their frequencies is 2:3? Answer: 9/4 MCQ35: The total work done by the string of a simple pendulum during one complete oscillation __ Answer: Equals the total energy of the pendulum