A magnetic field normal to a square metallic plate of area 4 m² varies linearly as shown. During t = 2 s to 4 s, the field changes from 4 × 10⁻³ T to 8 × 10⁻³ T. The induced emf is ______ mV. Image
Physics · Circular Motion
JEE Mains 11 April 2023 Shift 1 Morning Shift

Question

A magnetic field normal to a square metallic plate of area 4 m² varies linearly as shown. During t = 2 s to 4 s, the field changes from 4 × 10⁻³ T to 8 × 10⁻³ T. The induced emf is ______ mV. Image

Physics · Circular Motion

G1 Physics · Accepted Answer

Magnitude of induced emf is |ε| = A|dB/dt|. |dB/dt| = [(8−4)×10⁻³]/(4−2) = 2×10⁻³ T s⁻¹. |ε| = 4×2×10⁻³ = 8×10⁻³ V = 8 mV. Final value: 8