Problem $11$

A thin copper rod $1\mathrm{.}00$ m long has a mass of $50\mathrm{.}0$ g $.$ What is the minimum current in the rod that would allow it to levitate above the ground in a magnetic field of magnitude $0\mathrm{.}100$ T $?$

a$)1\mathrm{.}20$ A

b$)2\mathrm{.}40$ A

c$)4\mathrm{.}90$ A

d$)9\mathrm{.}80$ A

e$)$ None of those answers