
For the wire to remain stationary, the net force acting on it should be zero.
Balancing the forces along the incline,
mgsin45∘=ILBcos45∘
⇒I=(Lm)Bg
⇒I=0.15(0.45)(10)=30A
JEE Main 2022 — Physics Electromagnetism
As shown in the figure, a metallic rod of linear density 0.45kgm−1 is lying horizontally on a smooth incline plane which makes an angle of 45∘ with the horizontal. The minimum current flowing in the rod required to keep it stationary, when 0.15T magnetic field is acting on it in the vertical upward direction, will be
(Use g=10ms−2)

Held on 28 Jul 2022 · Verified 6 Jul 2026.
30A
15A
10A
3A
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