In an ammeter 0.2% of main current passes through the galvanometer. If resistance of galvanometer is G, the resistance of ammeter will be

A long straight wire carries a certain current and produces a magnetic field 2 $$ \times $$ 10^$$-$$4 Wb m^$$-$$2 at a perpendicular distance of 5 cm from the wire. An electron situated at 5 cm from the wire moves with a velocity 10⁷ m/s towards the wire along perpendicular to it. The force experienced by the electron will be (charge on electron 1.6 $$ \times $$ 10^$$-$$19 C)

A circular coil ABCD carrying a current 'i' is placed in a uniform magnetic field. If the magnetic force on the segment AB is $$\overrightarrow F $$, the force on the remaining segment BCDA is

When a proton is released from rest in a room, it starts with an initial acceleration $$a$$₀ towards west. When it is projected towards north with a speed $$v$$₀ it moves with an initial acceleration 3$$a$$₀ towards west. The an initial accelearation 3a₀ towards west. The an initial acceleration 3$$a$$₀ toward west. The electric and magnetic fields in the room are