A long solenoid has 300 turns/cm and carries a current of 2.3 A; its diameter is 2.5 cm. At its center we place an 80-turn, close-packed coil of diameter 2 cm. This coil is arranged so that B at th center of the solenoid is parallel to its axis. The current in the solenoid is reduced to zero and then raised to 2.5 A in the other direction at a steady rate over a period of 0.005 s. What induced emf appears in the coil while the current is being changed?