Electrical measuring instruments : grand prize Louisiana Purchase Exposition, St. Louis, 1904 (1904)
Leeds and Northrup Company · leaf 39
ixed resist-ance AB, as in other cases, the resistance whose terminals are AB isvaried, being in each case proportional to the current at the instant ofcontact. Thi^ is effected bj- having B fixed at the middle of M^N^ andmoving A to such a point on the spiral that the distance AB is propor-tional… … portional to the distance AB, and also to the current passing throughthe spiral MN. Since the former is proportional to I (the current), andthe latter is proportional to E {the electromotive force), the difference ofpotential AB, and, therefore, of PQ, is proportional to the product IE.which is the…
