NEET2018PhysicsMagnetic Effects of CurrentActual
A metallic rod of mass per unit length 0.5   kg   m - 1 is lying horizontally on a smooth inclined plane which makes an angle 30 o with the horizontal. The rod is not allowed to slide down by flowing a current through it when a magnetic field of induction 0 . 25   T is acting on it in the vertical direction. The current flowing in the rod to keep it stationary is
Options
- A14 . 76   A
- B5 . 98   A
- C7 . 14   A
- D11 . 32   A
Correct answer
D. 11 . 32   A
Step-by-step solution
For equilibrium of conductor i l B cos ⁡ θ = m g sin ⁡ θ i = m g l B tan ⁡ θ = m l g tan ⁡ θ B   i = 0.5 × 9.8 0.25 × 1 3 = 11.3  A .