JEE Advanced2024PhysicsMagnetic Effects of CurrentActual
A thin stiff insulated metal wire is bent into a circular loop with its two ends extending tangentially from the same point of the loop. The wire loop has mass m and radius r and it is in a uniform vertical magnetic field B₀ , as shown in the figure. Initially, it hangs vertically downwards, because of acceleration due to gravity g , on two conducting supports at P and Q . When a current I is passed through the loop,
Options
- A= r I B₀ /( mg )
- B=2 r I B₀ /( mg )
- C= r I B₀ /(2 m g)
- D=m g / ( r I B₀ )
Correct answer
A. = r I B₀ /( mg )
Step-by-step solution
aligned & Let loop makes angle with vertical. & in equilibrium _ net =0 & ₀= MB (90- )- mg . r =0 & I. r ^2 B ₀ = mg r.sin & = rIB ₀ mg & aligned