Advertisements
Advertisements
प्रश्न
- What name is given to a cylindrical coil of diameter less than its length?
- If a piece of soft iron is placed inside the coil mentioned in part (a) and current is passed in the coil from a battery, what name is then given to the device so obtained?
- Give one use of the device mentioned in part (b).
Advertisements
उत्तर
- Solenoid is a cylindrical coil of diameter less than its length.
- The device so obtained is electromagnet.
- It is used in electric bell.
APPEARS IN
संबंधित प्रश्न
The following diagram shows a spiral coil wound on a hollow carboard tube AB. A magnetic compass is placed close to it. Current is switched on by closing the key.
- What will be the polarity at the ends A and B?
- How will the compass needle be affected? Give reason.
State two ways by which the magnetic field due to a current carrying solenoid can be made stronger.
Why does a current carrying freely suspended solenoid rest along a particular direction? State the direction in which it rests.
Derive the expression for the heat produced due to a current ‘I’ flowing for a time interval ‘t’ through a resistor ‘R’ having a potential difference ‘V’ across its ends. With which name is the relation known? How much heat will an instrument of 12W produce in one minute if it is connected to a battery of 12V?
The adjacent diagram shows a small magnet placed near a solenoid. State whether the magnet is attracted or repelled, as the switch is pressed. Give a reason.
The magnetic field lines outside a bar magnet:
The diagram below shows a magnet moved near a coil along its axis. Which of the diagram shows correct flow of current during this motion?
The diagram below shows an insulated copper wire wound around a hollow cardboard cylindrical tube. Answer the questions that follow:
- What are the magnetic poles at A and B when the key K is closed?
- State two ways to increase the strength of the magnetic field in this coil without changing the coil.
- If we place a soft iron bar at the centre of the hollow cardboard and replace the DC source with an AC source then will it attract small iron pins toward itself when the current is flowing through the coil?
Differentiate between a circular coil and a solenoid.
Draw a neat diagram of a solenoid and name its various components.
