A battery is connected between two points `A and B` on the circumference of a uniform conducting ring of radius `r` and resistance `R` . One of the arcs `AB` of the ring subtends an angle `theta` at the centre . The value of the magnetic induction at the centre due to the current in the ring is

Options

A. proportional to `2(180^(@)- theta)`
B. inversely proportional to `r`
C. zero, only if `theta = 180^(@)`
D. zero for all values of `theta`

Answer

D

Explanation

`B_(1)` and `B_(2)` are equal and opposite as `B_(O)=0`