A J-shaped conducting rod rotates in its own plane with angular speed ω about end P in a uniform magnetic field B normal to the plane. If the two arms have lengths L and ℓ, the magnitude of emf between P and Q is:

Question

G1 Physics · Accepted Answer

For a conductor rotating about P in uniform perpendicular B, the potential at radius r relative to P is ΔV=½Bωr². Since PQ²=L²+ℓ², εₚq=½Bω(L²+ℓ²).