Given, a solenoid.Number of turns per unit length,n = 15 turns/cm = 1500 turns/m Area of the small loop, A = 2 cm2 = 2 x 10–4 m2Initial current, I1 = 2AFinal current, I2 = 4AΔt = 0.1sThe magnetic field associated with current I1,                     B1 = μ0 n I1 The magnetic field associated with current I2,                     B2 = μ0 n I2 The change in flux assosciated with change in current in solenoid, ∆ϕ = (B2-B1) A         = 4π×10-7×1500 × (4-2) × 2 × 10-4     = 7.6 × 10-7 weberThe induced EMF while current is changing,                    E = ∆ϕ∆t       = 7.6 × 10-70.1      = 7.6 × 10-6V