13. A solenoid of infinite length, having n circular turns per unit of length, is crossed by a current whose intensity varies over time according to the law i = Ct3, with C constant. What is the magnitude of the electric field induced at a point P inside the solenoid and distant r from its axis? i=ct³ B = μs wi Ei=- £r BB = 2 Cpui²r • E = 5μ0nr • There is no induced electric field because the solenoid is of infinite length XE= 310nCt2r 2 • E = 9 μ0nr

13. A solenoid of infinite length, having n circular turns per unit of length, is crossed by a current whose intensity varies over time according to the law i = Ct3, with C constant. What is the magnitude of the electric field induced at a point P inside the solenoid and distant r from its axis? i=ct³ B = μs wi Ei=- £r BB = 2 Cpui²r • E = 5μ0nr • There is no induced electric field because the solenoid is of infinite length XE= 310nCt2r 2 • E = 9 μ0nr