JEE Main2014PhysicsMagnetic Effects of CurrentActual
Three straight parallel current carrying conductors are shown in the figure. The force experienced by the middle conductor of length 25 ~cm is:
Options
- A3 10⁻⁴ ~N toward right
- B6 10⁻⁴ ~N toward right
- C9 10⁻⁴ ~N toward right
- DZero
Correct answer
A. 3 10⁻⁴ ~N toward right
Step-by-step solution
I₁=30 ~A I=10 ~A I₂=20 ~A Also given; length of wire Q=25 ~cm =0.25 ~m Force on wire Q due to wire R aligned &F_ Q R =10⁻⁷ 2 20 10 0.05 0.25 &=20 10⁻⁵ ~N (Towards left) aligned Force on wire Q due to wire P aligned &F_ Q P =10⁻⁷ 2 30 10 0.03 0.25 &=50 10⁻⁵ ~N (Towards right) & Hence, F_ net =F_ Q P -F_ Q R &=50 10⁻⁵ ~N -20 10⁻⁵ ~N &=3 10⁻⁴ ~N towards right aligned