Advertisements
Advertisements
प्रश्न
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.
Advertisements
उत्तर
The polarity of end X is south because current is flowing in clockwise direction at this end.
The polarity of end Y is north because current is flowing in anticlockwise direction at this end.
We have used clock face rule to determine the polarities.
APPEARS IN
संबंधित प्रश्न
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 a clockwise direction, then this end is a ........... pole.
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 S-pole is inserted?
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?
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?
|
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.
(ii) Global warming is a desirable aspect of the intensified greenhouse effect.
(c) Considering the relationship in the first pair, complete the second paie :
AgCI : White :: CuI2 : ___________
(ii) Global warming is a desirable aspect of the intensified greenhouse effect.
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.
Draw a neat labelled diagram to show the magnetic effect of electric current.
Identify the given figure, write the labels of it.

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?
______ are also used to remove splinters of steel or iron in hospitals dealing with eye injuries.
Edison used a ______ wire coil is a vacuum glass and discovered the first electric bulb in 1879.
Sailors use ______ to find direction in order to navigate on the sea.
An electric bell contains an ______, consisting of coils of insulated wire wound around
iron rods.
Using an electromagnet, you can make a working model of a railway signal as shown in figure.


