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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
An electric bell has an electromagnet.
Do you think an electromagnet can be used for separating plastic bags from a garbage heap? Explain.
Which effect of current can be utilised in detecting a current carrying wire concealed in a wall?
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
Name one device which works on the magnetic effect of current.
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 magnet is a rest in the coil?
If fuse of 250 mA, 500 mA, 1 A, 5 A and 10 A were available, which one would be the most suitable for protecting an amplifier rated at 240 V, 180 W?
Write the correct option by observing the figures.
(b) State whether the following statements are true or false:
(i) Magnetic poles exist in pairs.
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.
Magnetic effect of current was discovered by ______.
Why do we cover plug pin holes which are within the reach of children with cellotape or a plastic cover when not in use?
What do you mean by the magnetic effect?
An electric bell contains an ______, consisting of coils of insulated wire wound around
iron rods.
A student was asked to perform an experiment to study the force on a current carrying conductor in a magnetic field. He took a small aluminium rod AB, a strong horse shoe magnet, some connecting wires, a battery and a switch and connected them as shown. He observed that on passing current, the rod gets displaced. On reversing the direction of current, the direction of displacement also gets reversed. On the basis of your understanding of this phenomenon, answer the following questions:
- Why does the rod get displaced on passing current through it?
- State the rule that determines the direction of the force on the conductor AB.
-
- If the U-shaped magnet is held vertically and the aluminium rod is suspended horizontally with its end B towards due north, then on passing current through the rod from B to A as shown, in which direction will the rod be displaced?
- Name any two devices that use current carrying conductors and magnetic fields.
OR
Draw the pattern of magnetic field lines produced around a current carrying straight conductor held vertically on a horizontal cardboard. Indicate the direction of the field lines as well as the direction of current flowing through the conductor.
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?
Using an electromagnet, you can make a working model of a railway signal as shown in figure.
