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Subjects
Science State Board
Class 7
Electricity
Textbook questions
15.
Long answer I
Exercise condition:
4
m.
Explain the construction and working of an Telephone.
a
. The diaphragm is connected to a spring connecting to the
earpiece
cord
.
b
. The soft-iron bar becomes an
magnet
electromagnet
when a current travels through the wires.
c.
The earpiece's
diaphragm
cord
vibrates and produces sound.
d
. The diaphragm is comprised of a
magnet-attractive metal
electromagnetic material
.
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