本文利用推迟势求解了费曼在其物理学讲义中提出的行移场问题，相比于一般的电磁辐射问题，推迟势解法在本问题中具有以下特点：推迟势积分运算简单，可得到精确解析解；物理思想清晰，推迟势公式中蕴含的“电磁作用以有限速度c传播”这一物理观念在求解过程中得以充分展现.

 In this paper, we use the retarded potential to solve the traveling field problem proposed by Feynman in his lectures on physics. Compared with general electromagnetic radiation problems, the retarded potential solution has the following characteristics in this particular problem: (1) the retarded potential is simple to integrate, and an exact analytical solution can be obtained; (2) the physical idea is clear, and the physical concept of "electromagnetic action propagates with finite speed" contained in the retarded potential formula is fully demonstrated in the solving process.