Step-by-step explanation:
Area of square = 25^2 = 625 cm^2 or = 0.0625 m^2
number of turns = 100
Solenoid resistance = 10 ohms
now we know , Φ = B.A
where , Φ = magnetic flux, B= magnetic field strength, and A = area.
Φ = 10 × 0.0625 = 0.625 W
induced emf ε = dΦ/dt = d(BA)/dt =0
This is because both B and A are constants.
⇒ Induced current is also zero.
Replacing square by a circle will not change situation as the value of B and A will remain constant with time hence, no emf induced, so no current induced.