The magnetic field of given length of wire for single turn coil at its centre is B then its value for two turns coil for the same wire is

Two bar magnets having same geometry with magnetic moments M and 2M, are firstly placed in such a way that their similar poles are same side then its time period of oscillation is T₁. Now the polarity of one of the magnet is reversed then time period of oscillation is T₂, then

For a series LCR circuit the power loss at resonance is

The velocity of electromagnetic wave is parallel to