Physics Multiple Choice Questions on “Forced Oscillations and Resonance”.
1. What is the frequency with which forced periodic oscillations oscillate?
a) Frequency of forced oscillator
b) Their natural frequency
c) No specific frequency
d) Sum of frequency of forced oscillator & their natural frequency
Answer: a
Clarification: In the case of forced oscillations, the oscillations made by the body do not depend on their natural frequency, instead they oscillate with the frequency of the forced oscillator.
2. Resonance occurs when frequency of forced oscillations is close to natural frequency. True or False?
a) True
b) False
Answer: a
Clarification: Resonance is the phenomenon of oscillation with increased amplitude when frequency of forced oscillator is close to natural frequency. The reason for this increase in amplitude is that the vibrations of the external oscillator match with the vibrations of particles being oscillated and thus there is a net increase in vibrations.
3. Higher the value of damping constant, higher will be the amplitude at resonance. True or False?
a) True
b) False
Answer: b
Clarification: Higher the value of damping lesser will be the effect of forced oscillations in increasing the amplitude close to natural frequency. Therefore, higher the value of damping constant, lesser will be the amplitude at resonance.