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प्रश्न
What will be the effect on the working of an electric bell if instead of a direct current an alternating current is used?
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उत्तर
If electric bell is connected to a.c. instead of d.c. then bell will ring intermittently.
संबंधित प्रश्न
You are given an iron nail, a torch cell, and a long piece of insulated copper wire. With the help of a labelled neat diagram, describe in steps how you will make the nail, an electromagnet.
Show with the aid of a diagram how a wire is wound on a U-shaped piece of soft iron in order to make it an electromagnet. Complete the circuit diagram and label the poles of the electromagnet.
Fill in the blanks by writing (i) Only soft iron, (ii) Only steel, (iii) Both soft-iron and steel for the material of core and/or magnet.
Electromagnet ______.
A straight wire is held vertical and current is passed in it in the upward direction. A compass needle is kept near the wire in north of it. How is the needle deflected? What is the change in the deflection of the needle if the current in wire is reversed?
State two advantages of an electromagnet over a bar magnet.
What energy conversion takes place during the working of a d c motor?
State the factors that can increase the speed of rotation of the coil in a D.C. motor.
State the position of armature coil relative to the direction of magnetic field, in a D. C. motor when the deflecting couple acting an the coil is maximum.
(i) A straight wire conductor passes vertically through a piece of cardboard sprinkled with iron filings. Copy the diagram and show the setting of iron filings when a current is passed through the wire in the upward direction and the cardboard is tapped gently. Draw arrows to represent the direction of the magnetic field lines.
(ii) Name the law which helped you to find the direction of the magnetic field lines.
State the function of a split ring in D.C. motor.
