Class 12th

Electric field lines show how electric fields look and act but they are imaginary and have physics backing for their presence. They point the way a positive charge would move and their closeness shows field strength. Lines start on positive charges and end on negative ones. Crowded lines mean strong fields, spaced lines mean weak ones, and straight parallel lines mean uniform fields.

Electric field lines never cross as the field no matter what point you take will have only one direction. If two lines met, there would be two tangents at that point, meaning two directions for the same field. That would make the field undefined there, which is physically impossible.

Electric field lines never form closed loops as we should know the electrostatic field is conservative. In a conservative field, the work done in moving a charge around any closed path is zero. If lines formed loops, a charge would keep gaining energy along the path, which breaks this rule of zero net work.

W and Z bosons is responsible for the exchange particles of weak interaction.

Kindly go through the solution 

Kindly go through the solution