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Ernst Mach Education
Ernst Mach, born February 18, 1838 Moravia, Austrian Empire, died February 19, 1916, Haar, Germany. He established important principles of optics, mechanics, and wave dynamics. Mach was educated at home until the age of 14, then went to University of Vienna at 17. He received his doctorate in physics in 1860 and taught mechanics and physics in Vienna until 1864, when he became professor of mathematics at the University of Graz. Then Charles University in 1867. -
1860 Doppler Effect
Mach devised a simple apparatus that demonstrated that the Doppler effect was real, at least for sound. A six-foot tube with a whistle at one end was mounted so as to rotate in a vertical plane. When the listener stood in the plane of the axis of rotation no changes of pitch could be heard. But if the observer stood in the plane of rotation, fluctuations in pitch that corresponded to the speed of rotation could be heard. -
Pendulum Wave Machine
The pendulum wave machine composed of a series of pendulum with increasing bob length following a specific function. When released simultaneously, each pendulum oscillates with a slightly different period from the next, resolving a fascinating display of patterns resembling traveling waves, standing waves, beating and random motion. It demonstrates important concepts in classical physics. -
Mach's Principle
According to Mach, inertia that tendency of massive objects to move at constant velocity must depend on other bodies, because motion itself must be measured relative to other bodies. Rotations and accelerations along straight paths take place with respect to the reference frame of the distant stars and galaxies. The centrifugal forces that throw you to the side of an automobile as it rounds a corner arise because you are accelerating with respect to the distant matter in the universe.