A solenoid has N turns of area A distributed uniformly along its length. When the current in this solenoid increases at the rate of 2.0 A/s, an induced emf of 75 mV is observed. Suppose the spacing between the coils is doubled, so that the solenoid is twice as long but with the same area A and same number of turns N. When the current in this solenoid increases at the rate of 2.0 A/s, what is the magnitude of the induced emf?