What is the inductance reactance of a coil of 7H when connected to a 50Hz a.c circuit?

If a charge ion goes through a combined electric field E and magnetic field B, the resultant emergent velocity of the ion is 

In electrolysis, when same quantity of electricity is passed through different electrolytes, mass of substances deposited is proportional to 

If the rate of evaporation is y, and the rate of condensation is x, then, a vapour is saturated when 

The degree of precision of a vernier caliper is