A rectangular coil of N turns and of length a and width b is rotated at frequency f in a uniform magnetic field of magnitude B. as indicated in the figure. The coil is connected to co-rotating cylinders, against which metal brushes slide to make contact. The emf induced in the coil is given (as a function of time t) by 8 = 2xfNabB sin (2xft) = 8 sin (2xft). This is the principle of the commercial alternating-current generator. What value of Nab gives an emf with Eo - 278 V when the loop is rotated at 74.9 rev/s in a uniform magnetic field of 0.492 T? Sliding contacts T

A rectangular coil of N turns and of length a and width b is rotated at frequency f in a uniform magnetic field of magnitude B. as indicated in the figure. The coil is connected to co-rotating cylinders, against which metal brushes slide to make contact. The emf induced in the coil is given (as a function of time t) by 8 = 2xfNabB sin (2xft) = 8 sin (2xft). This is the principle of the commercial alternating-current generator. What value of Nab gives an emf with Eo - 278 V when the loop is rotated at 74.9 rev/s in a uniform magnetic field of 0.492 T? Sliding contacts T