Advertisements
Advertisements
Question
How does a solenoid behave like a magnet? Can you determine the north and south poles of a current-carrying solenoid with the help of a bar magnet? Explain.
Advertisements
Solution
A solenoid is a long coil of circular loops of insulated copper wire. Magnetic field lines are produced around the solenoid when a current is allowed to flow through it. The magnetic field produced by it is similar to the magnetic field of a bar magnet. The field lines produced in a current-carrying solenoid is shown in the following figure.
In the above figure, when the north pole of a bar magnet is brought near the end connected to the negative terminal of the battery, the solenoid repels the bar magnet. Since like poles repel each other, the end connected to the negative terminal of the battery behaves as the north pole of the solenoid and the other end behaves as a south pole. Hence, one end of the solenoid behaves as a north pole and the other end behaves as a south pole.
RELATED QUESTIONS
State the direction in which current-carrying freely suspended solenoid rests
The figure shows a solenoid wound on a core of soft iron. Will the end A be a N pole or S pole when the current flows in the direction shown?
The adjacent diagram shows a small magnet placed near a solenoid AB. Current is switched on in the solenoid by pressing the key K.
- State the polarity at the ends A and B.
- Will the magnet be attracted or repelled? Give a reason for your answer.
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.
A current carrying solenoid behaves like a ______.
- 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).
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?
Draw magnetic field lines in and around a current-carrying straight solenoid.
The diagram shows a current-carrying coil passing through a cardboard sheet. Draw three magnetic lines of force on the board.
State two factors on which magnitude of magnetic field at the centre depends.
Sketch the lines of force of the magnetic field of a solenoid. How does its field compare with that of a bar magnet?
Which of the following diagrams correctly shows the magnetic field produced by a current-carrying wire?
The factors on which one magnetic field strength is produced by current-carrying solenoids depends are
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?
When does a solenoid behave as a magnet? Draw the pattern of the magnetic field produced inside it showing the directions of the magnetic field lines.
How is a solenoid prepared?
Draw a neat diagram of a solenoid and name its various components.
Current is flowing through a coil as shown in the figure. Which one of the given figures will correctly depict the magnetic polarity and the direction of the lines of force along the axis of the coil?
