i) So as to create opposite polarity on the ends
ii) When a person speaks into the microphone at the other end, a varying electric current is set up having the same frequency as the sound waves. A similar electric current is caused to pass through the solenoid. This alters the strength of the magnetic field in the diaphragm. The diaphragm thus vibrates and reproduces the sound made on the microphone.
iii) The receiver would not work. The steel would become permanent magnet and so the speech current would not affect magnetic field.
johnmulu answered the question on April 19, 2017 at 07:31
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Date posted: April 19, 2017. Answers (1)
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Date posted: April 19, 2017. Answers (1)
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Date posted: April 19, 2017. Answers (1)
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Date posted: April 19, 2017. Answers (2)
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Date posted: April 19, 2017. Answers (1)
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Date posted: April 19, 2017. Answers (1)
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Date posted: April 19, 2017. Answers (1)
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Date posted: April 19, 2017. Answers (1)
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Date posted: April 19, 2017. Answers (1)
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Date posted: April 18, 2017. Answers (1)
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Date posted: April 18, 2017. Answers (1)
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Date posted: April 18, 2017. Answers (1)
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Date posted: April 18, 2017. Answers (1)
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Date posted: April 18, 2017. Answers (1)
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Date posted: April 18, 2017. Answers (1)