Magnetic Effects Of Current Question 167
Question: Two straight parallel wires, both carrying 10 ampere in the same direction attract each other with a force of $ 1\times {{10}^{-3}}N $ . If both currents are doubled, the force of attraction will be [MP PET 1994]
Options:
A) $ 1\times {{10}^{-3}},N $
B) $ 2\times {{10}^{-3}},N $
C) $ 4\times {{10}^{-3}},N $
D) $ 0.25\times {{10}^{-3}},N $
Show Answer
Answer:
Correct Answer: C
Solution:
$ F=\frac{{\mu_{0}}}{4\pi }\frac{2i_{1}i_{2}}{a}={{10}^{-3}}N $ When current in both the wires is doubled, then $ F’=\frac{{\mu_{0}}}{4\pi }\frac{2( 2i_{1}\times 2i_{2} )}{a}=4\times {{10}^{-3}}N $
BETA
