Test Index

CBSE Class 12 Physics 2023 Delhi Set 1 Paper

© examsnet.com
Question : 2 of 35
Marks: +1, -0
Two long parallel wires kept 2 m2\ \mathrm{m} apart carry 3 A3\ \mathrm{A} current each, in the same direction. The force per unit length on one wire due to the other is
Solution:     👈: Video Solution
i1  =i2=3 Ai_1\;=i_2=3\ \mathrm{A}
r  =2 mr\;=2\ \mathrm{m}
Fl  =  μ02π×  i2i2r\frac{F}{l}\;=\;\frac{\mu_0}{2\pi} \times\; \frac{i_2 i_2}{r}
  [μ02π=2×10−7NA−2]  \; \left[ \frac{\mu_0}{2\pi} = 2 \times 10^{-7} N_A^{-2} \right] \;
Or, Fl  =2×10−7×  3×32\frac{F}{l}\; = 2 \times 10^{-7} \times\; \frac{3 \times 3}{2}
∴ Fl  =9×10−7 N\frac{F}{l}\; = 9 \times 10^{-7}\ \mathrm{N}
Force per unit length =9.0×10−7 N/m= 9.0 \times 10^{-7}\ \mathrm{N/m}
Since, the currents are in same direction so there would be an attractive force between them.
© examsnet.com
Go to Question:
Prev Question
Next Question