Can groundwater be measured with copper pipes?

I feel that the iron bars swaying back and forth in the movie are exaggerated. In fact, if you know the people in the drilling team, you will find that they use two copper bars when looking for water, and their arms are parallel. When there is water in the local area, the copper bars will be closed together. The principle is that all metals have an electric charge. If there is water underground, the magnetic field in this place is different from that in other solid land. Two copper bars are parallel. When they enter a changing magnetic field, they will generate a weak current, and they will approach each other due to the electromagnetic force.