Balance Beam & Torque
Drag weights onto a seesaw and balance the torques on both sides.
Add weights, then drag them along the beam. Drag a weight off the beam to remove it. Drag the pivot to move it.
About the Balance Beam & Torque
Free torque simulator. Drag weights onto a balance beam, move the pivot, and see left and right torques, the tilt of the beam and when it balances. Built for physics, the balance beam & torque runs instantly in your browser: change a setting or drag an object and the result updates at once, so you learn by trying things out rather than only reading about them.
Drag weights onto a seesaw and balance the torques on both sides. Use it to explore physics ideas at your own pace, then check what you found against the key ideas further down this page.
How to use the Balance Beam & Torque
- Pick an option such as Ruler, Force arrows, Snap to 0.5 m to switch modes or load an example.
- Press "+ 5 kg", "+ 10 kg", "+ 20 kg", "Remove all" to start, reset or change what is happening.
- Where you see a glowing handle, object, weight or atom, drag it with your mouse or finger. Everything responds in real time.
- Watch the readouts and graphs update as you experiment, and compare what you see with the key ideas below.
Things to try
- Put a 20 kg weight 2 m left. Where must a 10 kg weight go to balance it?
- Drag the pivot off-centre and see how the beam behaves.
- Use three weights to balance the beam.
- Watch the beam swing and settle instead of jumping.
Key ideas you can learn
- Torque = force × distance from the pivot (τ = F d).
- The beam balances when the total clockwise torque equals the total anticlockwise torque.
- A lighter weight further from the pivot can balance a heavier weight closer in.
Where this is used in the real world
Levers and torque are used in wrenches, crowbars, cranes, seesaws and the human forearm. Balancing is also key to bridge and building design.
Who is this simulation for?
Physics students in middle school, high school and first-year university, teachers who want a quick demonstration for the projector, and anyone revising for exams. It works well for flipped classrooms because students can explore before the lesson.
For teachers: project it on the board, let students predict what will happen, then run it together. For students: change one thing at a time and write down what changes.
Frequently asked questions
How do you balance a seesaw?
Make the torques equal: m1 × d1 = m2 × d2. A child twice as heavy must sit half as far from the pivot.
What is torque?
The turning effect of a force. It equals the force times the perpendicular distance from the pivot.
Is the Balance Beam & Torque free to use?
Yes. It is completely free, with no signup, no download and no ads inside the simulation. It runs in your web browser.
Does the Balance Beam & Torque work on a phone or tablet?
Yes. It uses touch as well as the mouse, so you can drag objects with your finger. A larger screen makes the controls easier to see.