# The lever is acted upon by 1 forces, the arms of which are 0.1 m and 0.3 m.

**The lever is acted upon by 1 forces, the arms of which are 0.1 m and 0.3 m. The force acting on the short arm is 3 N. What must be the force acting on the long arm for the lever to be in balance?**

L1 = 0.1 m.

L2 = 0.3 m.

F1 = 3 N.

F2 -?

The condition for the equilibrium of the lever is the equality of the moments of forces that act from opposite sides of the lever: M1 = M2.

The moment of force M is called the product of the applied force F to the smallest distance from the application of force in the axis of rotation of the lever L, which is called the shoulder: M = F * L.

F1 * L1 = F2 * L2.

The force F2, which acts on the larger shoulder, will be expressed by the formula: F2 = F1 * L1 / L2.

F2 = 3 N * 0.1 m / 0.3 m = 1 N.

Answer: a force F2 = 1 N. acts on the larger arm of the lever, when it is in equilibrium.