JEE Advanced Model Paper 16 with solutions for online practice

A washer is made of metal having resistivity 10−7 Ωm. The washer has inner radius 1cm, outer radius 3 cm and thickness 1 mm. A magnetic field, oriented normal to theplane of the washer, has the time dependent magnitude B = (2t) tesla / sec. Find thecurrent (in ampere) around the washer