A circular loop of radius r is made of a wire of circular cross section of diameter ‘a’. When current I flows through the loop the magnetic flux linked with the loop due to self induced magnetic field is given by phi = mu_(0)r [ln((16r)/(a)) - (7)/(4)]l. The resistivity of the material of teh wire is rho and r gt gt a.Switch S is closed at time t = 0 so as to connect the loop to a cell of emf V. Find the current in the loop at time t.

A circular loop of radius r is made of a wire of circular cross sectio

1.	A circular loop of radius r is made of a wire of circular cross section of diameter ‘a’. When current I flows through the loop the magnetic flux linked with the loop due to self induced magnetic field is given by phi = mu_(0)r [ln((16r)/(a)) - (7)/(4)]l. The resistivity of the material of teh wire is rho and r gt gt a.Switch S is closed at time t = 0 so as to connect the loop to a cell of emf V. Find the current in the loop at time t.
Answer» Answer :`i = (Va^(2))/(8 RHO R) [1- e^(-t//tau)]` Where `tau = (mu_(0)a^(2))/(8rho) [In ((16r)/(a)) - (7)/(4)]`

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