Magnetic Effects Of Current Question 32
Question: The magnetic induction at a point P which is distant 4 cm from a long current carrying wire is $ {{10}^{-8}},Tesla $ . The field of induction at a distance 12 cm from the same current would be [CBSE PMT 1990; DPMT 2001]
Options:
A) $ 3.33\times {{10}^{-9}},Tesla $
B) $ 1.11\times {{10}^{-4}},Tesla $
C) $ 3\times {{10}^{-3}},Tesla $
D) $ 9\times {{10}^{-2}},Tesla $
Show Answer
Answer:
Correct Answer: A
Solution:
$ B=\frac{{\mu_{0}}}{4\pi }\cdot \frac{2i}{r} $
Þ $ \frac{B_{1}}{B_{2}}=\frac{r_{2}}{r_{1}} $
Þ $ \frac{{{10}^{-8}}}{B_{2}}=\frac{12}{4} $
Þ $ B_{2}=3.33\times {{10}^{-9}},Tesla $
BETA
