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प्रश्न
How does the magnetic effect of electric current help in the working of an electric bell? Explain with the help of a diagram.
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उत्तर
The door bell or the electric bell makes use of the principle of an electromagnet. A horseshoe type of electromagnet is used in an electric bell which is connected to the source of current through a switch. It has a metallic gong, a hammer to strike the gong and screw attached to a soft iron strip.
When the button is pressed, the circuit is complete and the hammer gets attracted to the gong thereby striking it to produce a ringing sound.
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संबंधित प्रश्न
Fill in the following blank with suitable words:
If a coil is viewed from one end, and the current flows in a clockwise direction, then this end is a ........... pole.
Which way does the wire in the diagram below tend to move?
A coil is connected to a galvanometer. When the N-pole of magnet is pushed into the coil, the galvanometer deflected to the right. What deflection, if any, is observed when:
the N-pole is removed?
A coil is connected to a galvanometer. When the N-pole of magnet is pushed into the coil, the galvanometer deflected to the right. What deflection, if any, is observed when:
the S-pole is inserted?
In the Activity shown below, how do we think the displacement of rod AB will be affected if
- current in rod AB is increased
- a stronger horse-shoe magnet is used
- length of the rod AB is increased?
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(b) State whether the following statements are true or false:
(i) Magnetic poles exist in pairs.
(ii) Global warming is a desirable aspect of the intensified greenhouse effect.
In the arrangement shown in Figure there are two coils wound on a non-conducting cylindrical rod. Initially the key is not inserted. Then the key is inserted and later removed. Then
______ cells cannot be recharged after use.
A wire with green insulation is usually the live wire of an electric supply.
A rectangular loop ABCD carrying a current I is situated near a straight conductor XY, such that the conductor is parallel to the side AB of the loop and is in the plane of the loop. If a steady current I is established in the conductor as shown, the conductor XY will ______.
