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प्रश्न
What is the function of a split ring in an electric motor?
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उत्तर
The split rings help to reverse the direction of current in the circuit. These are called the commutator.
संबंधित प्रश्न
An electric bell has an electromagnet.
Which effect of current can be utilised in detecting a current carrying wire concealed in a wall?
Fill in the following blank with suitable words:
If a coil is viewed from one end and the current flows in an anticlockwise direction, then this end is a ........... pole.
What is Maxwell's corkscrew rule? For what purpose is if used?
If the direction of electric current in a solenoid when viewed from a particular end is anticlockwise, then this end of solenoid will be:
(a) west pole
(b) south pole
(c) north pole
(d) east pole
Write the correct option by observing the figures.
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.
Draw magnetic field lines produced around a straight current carrying conductor passing through a cardboard. How will the strength of the magnetic field change when the point where magnetic field is to be determined is moved away from the conductor?
If the key in the given arrangement is taken out (the circuit is made open) and magnetic field lines are drawn over the horizontal plane ABCD, the lines are ____________.
What is that instrument which can detect the presence of electric current in a circuit?
Unscramble the following words:
HTRCO
Paheli does not have a night lamp in her room. She covered the bulb of her room with a towel at the night to get dim light. Has she taken the right step? Give one reason to justify your answer.
Why do we cover plug pin holes which are within the reach of children with cellotape or a plastic cover when not in use?
______ cells cannot be recharged after use.
What are MCBs? How do they work?
An electric bell contains an ______, consisting of coils of insulated wire wound around
iron rods.
