MCQ
When equal current is passed through two coils, equal magnetic field is produced at their centres. If the ratio of number of turns in the coils is $8: 15$, then the ratio of their radii will be
- A$1: 1$
- B$15: 8$
- ✓$8: 15$
- D$1: 2$
✓
Answer
Correct option: C.
$8: 15$
c
(c)
(c)
$B_1=B_2$
$\frac{\mu_0 n_1 i}{2 r_1}=\frac{\mu_0 n_2 i}{2 r_2}$
$\frac{n_1}{n_2}=\frac{8}{15}=\frac{r_1}{r_2}$
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