Advertisements
Advertisements
प्रश्न
What is the function of a split ring in an electric motor?
Advertisements
उत्तर
The split rings help to reverse the direction of current in the circuit. These are called the commutator.
संबंधित प्रश्न
Will the compass needle show deflection when the switch in the circuit shown by figure is closed?
An electromagnet does not attract a piece of iron.
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.
For the coil in the diagram below, when the switch is pressed:
(a) what is the polarity of end A?
(b) which way will the compass point then?
Name one device which works on the magnetic effect of current.
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?
(ii) Global warming is a desirable aspect of the intensified greenhouse effect.
Identify the given figure, write the labels of it.
Explain the magnetic field created around a straight current carrying conductor with the help of a diagram.
A soft iron bar is introduced inside the current-carrying solenoid. The magnetic field inside the solenoid ____________.
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
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?
Boojho made an electromagnet by winding 50 turns of wire over an iron screw. Paheli also made an electromagnet by winding 100 turns over a similar iron screw. Which electromagnet will attract more pins? Give reason.
______ cells cannot be recharged after use.
An electric bell contains an ______, consisting of coils of insulated wire wound around
iron rods.
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 ______.
Make four electromagnets with 20, 40, 60 and 80 turns. Connect them one by one to a battery of 2 cells. Bring the electromagnet near a box of pins. Count the number of pins attracted by it. Compare the strengths of the electromagnets.
