A horizontal power lines carries current in east to west direction. What is the direction of magnetic field due to the current at a point above and at a point below the power line?
Important Questions on Magnetic Effects of Electric Current
In the figure below, identify the poles marked and as north pole or south pole. Give reason for your answer.
(a) Describe an activity to draw a magnetic field line outside a bar magnet from one pole to another.
(b) List any two properties of magnetic field lines.
What happens to the deflection of the compass needle placed at a point near current-carrying straight conductor
(a) If the current is increased,
(b) If the direction of current in the conductor is changed,
(c) If compass is moved away from the conductor?
A student performs an experiment to study the magnetic effect of current around a current-carrying straight conductor. He reports that
(a) For a given battery, the degree of deflection on N-pole decreases when the compass is kept at a point farther away from the conductor.
(b) The direction of deflection on N-pole of compass needle kept at a given point near the conductor remains unaffected even when the terminals of the same battery sending current in the wire are interchanged. Which of the two observations appears to be wrong and why?
(a) What are factors on which the magnetic field produced by a current-carrying conductor depend?
(b) What happens to the magnetic field lines due to a current-carrying conductor, when the current is reversed? State the rule which gives this direction and current.
Briefly explain an activity to plot the magnetic field lines around a bar magnet. Sketch the field pattern for the same specifying field directions. A region 'A' has magnetic field lines relatively closer than another region 'B'. Which region has stronger magnetic field? Give reason to support your answer.
