Question 10
- List two factors that affect the frequency of a vibrating stretched string.
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- The diagram above illustrates a sonometer. Identify each of the parts labelled P and Q.
- State two functions of a sonometer.
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Explain each of the following terms:
- fundamental note;
- overtones;
- harmonics.
- A sonometer wire of length l vibrates at a frequency f 350 Hz. When the length of the wire is increased by 15 cm, the wire vibrates at 280 Hz under constant tension. Determine l.
Observation
The expected answer is:
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Factors that affect the frequency of vibrating stretched strings
- Length of the string
- Tension in the string
- Mass per unit length of the string
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- Identification of labelled parts on sonometer
P - Pulley
Q - Bridges -
Functions of a sonometer
Used to- determine the frequency of tuning forks
- verify the laws of vibrating strings
- measure the frequency of an a.c. supply
- Identification of labelled parts on sonometer
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Explanation of terms
- Fundamental note - the sound of lowest frequency or pitch
- Overtone - a note of frequency higher than the fundamental frequency of sound.
- Harmonics - notes which are produced by multiples of the fundamental frequency.
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Harmonics - notes which are produced by multiples of the
fundamental frequency.