BITSAT 2010
- Exam
- BITSAT
- Year
- 2010
- Subject
- Physics
- Chapter
- Magnetic Effects of Current
BITSAT 2010 · Physics · Magnetic Effects of Current
The magnetic field at the origin due to the current flowing in the...
The magnetic field at the origin due to the current flowing in the wire is
Options
- A-\frac{\mu_{0}\mathrm{I}}{8 \pi \mathrm{a}}(\hat{\mathrm{i}}+\hat{\mathrm{k}})
- B\frac{\mu_{0}\mathrm{I}}{2 \pi \mathrm{a}}(\hat{\mathrm{i}}+\hat{\mathrm{k}})
- C\frac{\mu_{0}\mathrm{I}}{8 \pi \mathrm{a}}(-\hat{\mathrm{i}}+\hat{\mathrm{k}})
- D\frac{\mu_{0}\mathrm{I}}{4 \pi \mathrm{a} \sqrt{2}}(\hat{\mathrm{i}}-\hat{\mathrm{k}})
Correct answer
C. \frac{\mu_{0}\mathrm{I}}{8 \pi \mathrm{a}}(-\hat{\mathrm{i}}+\hat{\mathrm{k}})
Step-by-step solution
\mathrm{B}_{\mathrm{OD}}=0, \mathrm{ B}_{\mathrm{OB}}=0\mathrm{ B}_{\mathrm{AB}}=\frac{\mu_{0}\mathrm{I}}{4 \pi \mathrm{a} \sqrt{2}}\left[\cos 45^{{}^{\circ}}(-\hat{\mathrm{i}})+\cos 45^{{}^{\circ}} \hat{\mathrm{k}}\right]=\frac{\mu_{0}\mathrm{I}}{8 \pi \mathrm{a}}(-\hat{\mathrm{i}}+\hat{\mathrm{k}})