KCET2021PhysicsMagnetic Effects of Current
Two parallel wires in free space are 10 ~cm apart and each carries a current of 10 ~A in the same direction. The force exerted by one wire on the other [per unit length] is
Options
- A2 10⁻⁴ Nm ⁻¹ [attractive]
- B2 10⁻⁷ Nm ⁻¹ [attractive]
- C2 10⁻⁴ Nm ⁻¹ [repulsive]
- D2 10⁻⁷ Nm ⁻¹ [repulsive]
Correct answer
A. 2 10⁻⁴ Nm ⁻¹ [attractive]
Step-by-step solution
Given, aligned &r=10 ~cm =10 10⁻² ~m &I₁=I₂=10 ~A aligned Force exerted by one wire on the other per unit length is given as F l = ₀ I₁ I₂ 2 r Substituting the given values, in the above relation, we get F l = 4 10⁻⁷ 10 10 2 10 10⁻² =2 10⁻⁴ Nm ⁻¹ Since, the current is flowing in the same direction, so the force will be attractive in nature.