Two identical long conducting wires $$AOB$$ and $$COD$$ are placed at right angle to each other, with one above other such that $$O$$ is their common point for the two. The wires carry $$I$$₁ and $$I$$₂ currents, respectively. Point $$P$$ is lying at distance f from $$O$$ along a direction perpendicular to the plane containing the wires. The magnetic field at the point $$P$$ will be

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