Problem 7.9 Investigate the effect of using different combinations of rf systems to tip the spins and measure the resulting signal. a) Assume two identical spins are excited by a uniform field, such that they both receive a perfect /2-rotation into the transverse plane. What will be the relative difference in the signal between the two spins if Breceive (spin 1) = C, a constant, and Breceive (spin 2) = 1/2 C? b) Assume now that the two spins from (a) are excited by different trans- mit fields. The first spin experiences Bransmit (spin 1) = C', another con- stant, and receives a 7/2 flip. The second spin only experiences a field of Bransmit (spin 2) = 1/2 C, and therefore is not rotated by the same angle. If Breive is identical for the two spins, what is the relative difference in their measured signal? c) It appears from the preceding problems that if only one of the transmit and receive fields is inhomogeneous, but not both, then it might be best to transmit with an inhomogeneous rf field, and receive with a homogeneous field. However, this is not how experiments are normally performed. Explain why this might be the case. Hint: Recall that the received signal depends upon BB/I and preview Ch. 15.