Physics
(a) How would you demonstrate magnetic effect of current? By whom it was discovered?
(b) For the current carrying solenoid as shown below, draw magnetic field lines. Explain that out of the three points A, B and C at which point, the field strength is maximum and at which point it is minimum.
Answer
(a) If a compass needle is placed in the vicinity of the current carrying wire, the needle is found to deflect in a definite direction. This was discoverd by Hans Oersted.
(b) Below diagram shows the magnetic field lines for the current carrying solenoid:
The magnetic field strength is maximum at point A and minimum at point B because magnetic field is strong where magnetic field lines are crowded and is weak where magnetic field lines are far apart.
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