Grandpa Fenn's Workshop

The Lever Lab

A plank and a pivot. With these two things Grandpa lifted the whole back end of his truck.

Grandpa Fenn at the workshop door with his field notebook

Balance it

Pick a weight. Tap a spot on the plank to put it there. Tap a weight on the plank to take it off. Slide the pivot to move the balance point.

Weights:
Left push0
Right push0
VerdictEmpty

Start with one crate on each side.

Grandpa nods. You just did what a lever does best.

Why it works

Every crate pushes the plank down. A crate far from the pivot pushes harder than the same crate close to it.

The push is the weight times the distance. Put a small weight far out and it can match a big weight close in.

That is the secret of a lever. You give up distance and you gain strength.

Grandpa. A crowbar is a lever. So is a spoon prying a lid. So is a wheelbarrow. Find the pivot and you find the trick.
Toby Fenn with his notebookToby counts the spaces

Grandpa's notebook

A weight pushes harder the farther it sits from the pivot.

A plank balances when the push on the left matches the push on the right.

A long reach lets a small weight lift a big one.

Big word for the day. Lever. A stiff bar that turns around a pivot.

More machines are waiting on the bench.

Try the Pulley Lab

Back to the Chain Reaction Bench