An electron is passing near a ring, then direction of induced current in ring is:

CONCEPT:

• Lenz's Law: This law states that the direction of the current induced in a conductor by a changing magnetic field is such that the magnetic field created by the induced current opposes the initial changing magnetic field.
• The direction of the magnetic field due to the current-carrying conductor can find out by the right-hand thumb rule. 
  • If you wrap your right hand’s fingers around the wire with your thumb pointing in the direction of the current, then the direction in which the fingers would curl will give the direction of the magnetic field.

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In diagram I = Current and B = Magnetic field

​EXPLANATION:

• We know that the direction of the current is taken as opposite to the direction of motion of the electron. In question, the electron is moving from left to right so the direction of the current will be right to left.
• According to the right-hand thumb rule, the direction of the magnetic field on the ringside due to the motion of the electron will be perpendicular to the paper and inward.
• In the diagram, the electron is firstly coming closer to the ring, and then it is going away from the ring so the magnetic field associated with the ring due to the motion of the electron is firstly increasing and then decreasing.
• So when the electron is coming closer to the ring the direction of the induced current in the ring will be such that it will try to decrease the increasing magnetic field.
• For this, the direction of the magnetic field due to the induced current in the ring should be opposite to the direction of the magnetic field due to the electron. So the direction of the magnetic field due to the induced current in the ring will be perpendicular to the paper and outward. For this, the current in the ring will be anticlockwise.
• So when the electron is going away from the ring the direction of the induced current in the ring will be such that it will try to increase the decreasing magnetic field.
• For this, the direction of the magnetic field due to the induced current in the ring should be along the direction of the magnetic field due to the electron. So the direction of the magnetic field due to the induced current in the ring will be perpendicular to the paper and inward. For this, the current in the ring will be clockwise.
• So firstly the direction of the induced current in the ring is anticlockwise and then it is clockwise.
• Hence, option 3 is correct.