John Trowbridge (August 5, 1843 – February 18, 1923) was an American physicist, noted for his research into electricity and magnetism, and for his innovations in scientific education.

Born into a long-established New England family, John Trowbridge could trace his roots in Massachusetts and Connecticut back to the early seventeenth century.

His father, John Howe Trowbridge, was a graduate of Harvard Medical School, but did not pursue a professional career, having inherited a sufficient fortune to finance a life of ease.

Also an accomplished pianist and writer, a career in arts and letters seemingly beckoned, but pragmatic considerations led him ultimately to pursuit of the sciences.

[2] Despite heavy teaching and administrative responsibilities, Trowbridge nevertheless published prolifically on his main research topics of electricity and magnetism, including works on the analysis of solar spectra and on the generation of Röntgen radiation (X-rays).