Question

A straight horizontal wire of mass 10 mg and length 1m carries a current 2A what minimum magnetic field should be applied in the region so that the
magnetic force on the wire may balance its weight
(A)
fi+f2
(B)
2f1f2
F + f2
(C) V5152
(D) I= 5 sin (100t + 5) amp​

Answer 1

Answer:

I guess the options they have given are wrong

Explanation:

Mass = 10mg = 10^-5kg

Length = 1m

I = 2A,

B = ?

Now, Mg = ilB

Mg/il=B

B=(10^-5×9.8)/(1×2)

B=4.9×10^-5