Practice question

Given: A wheel with 5 spokes of 0.65 m each rotates at 42 rpm in a 0.7 T field. What is the induced emf? Formula: omega = 2π × 42/60 = 1.4π rad/s. Substitution & Calculation: ε = 1/2 B omega R² = 1/2 × 0.7 × 1.4π × (0.65)² = 0.623 V approx 0.62 V . Final Result: The computed value matches expected outcome and confirms correct choice as per latest NCERT 2026-27.