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The Atwood machine (or Atwood's machine) was invented in 1784 by Rev. George Atwood as a laboratory experiment to verify the mechanical laws of uniformly accelerated motion. Atwood's machine is a common classroom demonstration used to illustrate principles of physics, specifically mechanics.

The Atwood Machine

The Atwood machine (or Atwood's machine) was invented in 1784 by Rev. George Atwood as a laboratory…

"Atwood's Machine. This difficulty has however been overcome by a curious piece of machinery invented by Mr. Atwood. This consists of an upright pillar, with a wheel on the top. The weights A and B are of the same size and are made to balance each other, exactly, being connected by a thread passing over the wheel. The ring R admits the weight A, to fall through it in its passage to the stage S, on which it rests. The right and stage slide up and down, and are fastened by a thumb screw. The pillar is a graduated scale, and M is a small bent wire, weighing a quarter of an ounce, and longer than the diameter of the ring." —Comstock, 1850

Atwood's Machine

"Atwood's Machine. This difficulty has however been overcome by a curious piece of machinery invented…

"Machine designed by Atwood to allow the measurement and calculation of the velocities of falling bodies at various points accurately and easily." —Quackenbos 1859

Atwood's Machine

"Machine designed by Atwood to allow the measurement and calculation of the velocities of falling bodies…

"The Atwood machine consists of a wheel or pulley, R, over the grooved edge of which are balanced two equal weights suspended by a long silk thread which is both light and strong. The axle of this wheel is preferably supported upon the circumfrences of four friction wheels, r, r, r', r', for greater delicacy of motion. As the thread is so light that its weight may be disregarded, it is evident that the weights will be in equilibrium whatever their position." — Avery, 1895

Atwood Machine

"The Atwood machine consists of a wheel or pulley, R, over the grooved edge of which are balanced two…