Physics Figures Pulley Generator
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Pulley diagrams: Atwood machines, tables, ramps and block and tackle

The Pulley Generator draws objects tied by string over pulleys, in four setups: an Atwood machine, with two masses hanging over one fixed pulley; a block or cart on a table, tied over a pulley at its edge to a hanging mass; a block or cart on a ramp, tied over a pulley at its top to a hanging mass; and a block and tackle, with 1 to 4 strands holding up a load. Strings are always drawn taut.

Turn on tension, gravity, the normal force and friction to draw the forces for a Newton’s second law problem, and an acceleration arrow for each object. Every label can be written, a blank line for students, or left off.

What you can set

  • The setup: Atwood machine, table and hanging mass, ramp and hanging mass, or block and tackle
  • Each object’s label and size; on a table or ramp, a block or a cart; in an Atwood machine, which side hangs lower
  • The ramp’s angle, 10° to 60°, and its label, and a smooth or rough surface
  • In a block and tackle, 1 to 4 strands holding up the load
  • Tension along the strings, gravity on each object, the normal force and friction on the object on a table or ramp, and each object’s acceleration
  • Mirror, to flip the figure left to right, and color for slides

Copying, printing and sharing

Copy the figure straight into a test, worksheet or slide, or download it as a PNG or SVG. Printing the page prints just the figure. Share link copies the page’s address with your settings in it, so anyone who opens it sees this exact figure, and presets save settings you use often in your browser. It’s free, with no sign-up.

Example figures

Frequently asked questions

What is an Atwood machine?

Two masses hanging from one string over a fixed pulley. With a light string and a frictionless pulley, the heavier mass falls and the lighter one rises, both with acceleration a = (m₂ − m₁)g / (m₁ + m₂), where m₂ is the heavier mass.

Why is every tension arrow labeled T?

With a light string over a light, frictionless pulley, the tension is the same all along the string, so every tension arrow has the same label. Change it to a blank line if students should work that out.

How does a block and tackle make lifting easier?

The load is held up by several strands of one rope, each pulling up with the same tension. With n strands holding the load, the effort at the free end is the load’s weight divided by n, ignoring friction and the pulleys’ weight, but the rope has to be pulled n times as far. That n is its ideal mechanical advantage.

Which way does friction point on the block?

Against the way the block slides or would slide. When the hanging mass pulls the block toward the pulley, friction points away from it. Choose Toward the pulley or Away from it.

Can I draw the forces on just one of the objects?

Use the Free Body Diagram Generator, which draws one body with only the forces on it, like the tension and weight on the hanging mass.

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