The synchronous precession of magnetic spins induces an oscillating voltage in the coil that decays with a characteristic T2 time constant for each spin type as the spins fall out of synchrony.

• 磁性自旋的同步进动现象可产生振荡电压，然后各原子核会逐渐开始不同步自旋，此电压逐渐消退所经历的时间，称做时间常数T2。