Radioactive isotopes are produced in a nuclear physics experiment at a constant rate dN/dt = R. An inductor of inductance 100 mH, a resistor of resistance 100 Ω and a battery are connected to form a series circuit. The circuit is switched on at the instant the production of radioactive isotope starts. It is found that i/N remains constant in time where i is the current in the circuit at time t and N is the number of active nuclei at time t. Find the half-life of the isotope.

Given, Resistance R= 100Ω

Inductance L= 100mH


Let initial current be i˳


After time t,


Current at time t is given by



(where R is the resistance, L is the inductance)


So,


As the ratio should be independent of time,





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