Most Important Selected Qs for JEE AdvancedPhysicsMagnetic Effects of Current
An infinitely long wire carrying a current I in vertically upward direction ( y -direction) is placed near the surface of earth as shown in figure. Neglect the earth's magnetic field : At some time t a particle is at point A ( a , 0) and moving towards origin with velocity V . If the acceleration of particle at point A is 2 g in downward direction then :
Options
- Aparticle is negatively charged
- Bparticle is positively charged
- Cmagnitude of charge on the particle is ( amg ₀ VI )
- Dmagnitude of charge on the particle is ( 2 amg ₀ VI )
Correct answer
D. magnitude of charge on the particle is ( 2 amg ₀ VI )
Step-by-step solution
B = ₀ I 2 a by the direction of force particle is positively charge. Now aligned & mg + ₀ I 2 a q v =2 mg & ₀ I 2 a qv = mg q = 2 mga ₀ IV aligned