Opechowski was born in
Warsaw as the son of Edward Opechowski, an electrical engineer, and Wanda Pelz, a social activist. He studied mathematics and physics at the
University of Warsaw from 1931 to 1935. In 1935, he completed a research internship in France at the
University of Paris and in the Netherlands, where he was an assistant for
Hans Kramers and later studied under
Adriaan Fokker and
Léon Rosenfeld. After returning to Poland in 1937, he became an assistant of
Czesław Białobrzeski at the Department of Theoretical Physics of the
University of Warsaw, and also started teaching at the university. Opechowski moved to
Leiden University in 1939 and remained working there until 1945. This was followed by another research position at the
Philips Natuurkundig Laboratorium from 1945 to 1948 in
Eindhoven. and remained there for the rest of his career. After retiring in 1976, he continued to work there as an emeritus professor. == Honors and awards ==