Given, radius of circular coil, r = 8.0 cm = 0.08 m Number of turns, N = 20 Angular speed of coil, ω=50‌rad‌s−1 Magnetic field, B=3.0×10−2T The maximum emf induced in a coil can be expressed as ε=ω‌NBA Here, A is the area of coil. ε=NB‌ω(πr2) Substituting the given values, we get ε=20×3.0×10−2×50×π×(0.08)2 =60.3×10−2V ≃60×10−2V