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प्रश्न
Name any two appliances which works on the phenomenon of magnetic effect of electric current.
Name any three appliances based on the magnetic effect of electric current.
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उत्तर
Ammeter, microphone, electric bell, galvanometer, loud speaker, electric generator, electric motor, telephone receiver, radio, stereo speaker.
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संबंधित प्रश्न
Which effect of current can be utilised in detecting a current carrying wire concealed in a wall?
Name the scientist who discovered the magnetic effect of current.
What is Maxwell's corkscrew rule? For what purpose is if used?
The magnetic effect of current was discovered by:
(a) Maxwell
(b) Fleming
(c) Oersted
(d) Faraday
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?
Which way does the wire in the diagram below tend to move?
When the switch S is closed in the figure given below, the pointer of the galvanometer moves to the right.
If S is kept closed, will the pointer:
(a) return to zero?
(b) stay over on the right?
(c) move to the left and stay there
(d) move to and fro until S is opened
Write the correct option by observing the figures.
(c) Considering the relationship in the first pair, complete the second paie :
AgCI : White :: CuI2 : ___________
(b) State whether the following statements are true or false:
(i) Magnetic poles exist in pairs.
Explain the magnetic field created by a current around a conductor from the figure.
What is that instrument which can detect the presence of electric current in a circuit?
A magnetic compass shows a deflection when placed near a current carrying wire. How will the deflection of the compass get affected if the current in the wire is increased? Support your answer with a reason.
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.
An electric bell contains an ______, consisting of coils of insulated wire wound around
iron rods.
The figure given below shows the magnetic field around the conductor. Study it and answer the questions:
- What changes are caused by increasing current?
- What do you see when the magnetic needle is kept a little away from the wire?
- In the second part of the figure, the iron filings arrange themselves in a circular manner around the wire. Why does this happen?
As shown in the diagram an aluminium rod 'AB' is suspended horizontally between the two poles of a strong horse shoe magnet in such a way that the axis of rod is horizontal and the direction of the magnetic field is vertically upward. The rod is connected in series with a battery and a key.
State giving reason:
- What is observed when a current is passed through the aluminium rod from end B to end A?
- What change is observed in a situation in which the axis of the rod 'AB' is moved and aligned parallel to the magnetic field and current is passed in the rod in the same direction?
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.
