Page 133 - Science Class 07

Uses in Memory Storage Devices and
Computer Hardware

The data in ebook gadgets and phones are
stored in the electromagne c format in the
form of bits and bytes. The computer hardware
is also having a magne c tape which works on
the principle of electromagne sm. Even in the
olden days, electromagnets had a huge role in
the data storage of VCP and VCR.

Uses in Communica on Devices and Power
An Electric Bell
Circuits

Without electromagnets, the mobiles and the Working
telephones we use to make phone calls over Electric current flows through the coil when the
long distance could not have taken shape. The switch is ON, and the iron core acts as an
electromagne c pulses and the interac on of electromagnet. The iron core a racts the
the signals make the mobiles and telephones hammer towards it. The hammer hits the bell
very handy. and produces a sound. The circuit breaks at the

ELECTRIC BELL screw contact when the hammer moves
towards the iron core. At this point, the iron
Electric bell is a common device in which the
core ceases to be an electromagnet. The
property of electromagnet is used.
hammer is pulled back to its original posi on
Construc on
due to the spring ac on of the steel rod, and
An electric bell consists of a horseshoe-shaped then touches the contact again to complete the
electromagnet. It is connected with an circuit. The circuit is completed and current
armature with its one end. The armature is flows through the coil again, and the hammer

connected with a contact screw and the one strikes the bell again. The process repeats itself
end of this contact screw is the switch. The and you hear a ringing sound since the hammer
other end of the armature is connected with a keeps hi ng the bell, un l the switch is
hammer. A gong is fixed just near the hammer. released.

Electricity : Flow of electrons along a conductor

Energy : Capacity to do work
Electric circuit : The path through which an electric current passes
Conductor : Materials which can allow electric current to pass through them

Insulator : Materials which cannot allow electric current to pass through them
Battery : The source of the electric current
Resistor : A device which gives resistance to electric flow

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