He thought the best response was to devise a device that could read faint signals. The galvanometer, first invented in 1802, was a means of detecting electric current. It consisted of a needle ...

Ketika magnet dikeluarkan dari kumparan, jarum galvanometer ikut bergerak ... Kumparan adalah rangkaian kawat yang dililit hingga membentuk gulungan. Kumparan menjadi salah satu komponen penting ...