Question

When a vibrating tuning fork is placed on a table, a large sound is heard. This is due to ________.
A) Forced Vibrations
B) Resonance
C) Beats
D) Reflection

Answer 1

Hint: Sound happens when there is a to and fro motion of an object, when an object oscillates on its own then the sound happens. The tuning fork is soundless when it is in an ideal state and we bang the tuning fork on the table or on any solid surface and bring the tuning fork closer to our ear when we hear a sound.

Complete solution:
Tuning fork as the name suggests is a device that is used for tuning musical instruments. It is a U-shaped device that is made up of metal. It is used for producing a fixed tone. It is a type of resonator and unlike other resonators it gives out a pure sound. A resonator is a device which oscillates naturally at greater amplitudes at a given frequency, these frequencies are called resonant frequencies. Resonance is a phenomenon in which a vibrating system forces another system which is around it to vibrate with greater amplitude at a given frequency whereas a forced vibration is a phenomenon in which an alternating force or motion of an object or a system is applied to a system of a mechanical nature, in forced vibration the force is repeatedly applied to a mechanical system. Here, a good example of resonance is when we bang the tuning fork on the table and bring it closer to our ear the air around the fork starts to vibrate and then we can hear the sound. Similarly, a good example of a forced vibration is when we put an already vibrating tuning fork on the table and we hear a large sound.

Final answer is option A. When a vibrating tuning fork is placed on a table, a large sound is heard. This is due to forced vibrations.

Note: Here, first explain about tuning fork, give a brief about its purpose and its construction. Also, explain about resonance and frequency and differentiate between them by giving an example for each of the phenomena.