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प्रश्न
Draw a neat labelled diagram to show the magnetic effect of electric current.
उत्तर
Current flowing in clockwise direction-
Current flowing in anticlockwise direction-
APPEARS IN
संबंधित प्रश्न
Will the compass needle show deflection when the switch in the circuit shown by figure is closed?
Fill in the following blank with suitable words:
The magnetic effect of a coil can be increased by increasing the number of ........... increasing the ........... or inserting an ........... core.
The direction of current flowing in the coil of an electromagnet at its two ends X and Y are as shown below:
What is the polarity of end X?
What is the polarity of end Y?
Name and state the rule which you have used to determine the polarities.
Which way does the wire in the diagram below tend to move?
The north pole of a long bar magnet was pushed slowly into a short solenoid connected to a galvanometer. The magnet was held stationary for a few seconds with the north pole in the middle of the solenoid and then withdrawn rapidly. The maximum deflection of the galvanometer was observed when the magnet was ______.
How should the electric lamps in a building be connected so that the switching on or off in a room has no effect on other lamps in the same building?
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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What is the function of a split ring in an electric motor?
(b) State whether the following statements are true or false:
(i) Magnetic poles exist in pairs.
Answer the following question:
State the effect on the magnetic needle in Oersted’s experiment when:
(a) the current is passed through the wire.
(b) the current through the wire is increased
(c) the current through the wire is reversed.
Read the given passage and answer the following questions:
The home electrical connection consists of ‘live’, ‘neutral’ and ‘earth’ wires. The ‘live’ and the ‘neutral’ wires have potential difference of 220 V. The ‘earth’ is connected to ground. Due to a fault in the equipment or if the plastic coating on the ‘live’ and the ‘neutral’ wires gives a way the two wires come in contact with each other and a large current flows through it producing heat. If any inflammable material (such as wood, cloth, plastic, etc.) exists around that place it can catch fire. Therefore a fuse wire is used as a precautionary measure.
- Name the two wires having potential difference of 220 V.
- What is a short circuit?
- Write the function of a fuse.
A soft iron bar is introduced inside the current-carrying solenoid. The magnetic field inside the solenoid ____________.
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 ____________.
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 ______.
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 pinholes which are within the reach of children with sellotape 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.
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?
