Determine the force F1 required to maintain the balance of the lever if the force F2 is equal to 120N.

Determine the force F1 required to maintain the balance of the lever if the force F2 is equal to 120N. neglect the weight of the lever.

Let’s write down briefly given:

F2 = 120 N.

You need to find:

F1 -?

There should be a drawing for the task. As it is not attached to the condition, it was not difficult to find it on the Internet. The tasks were solved according to this figure.

Let’s start the solution by remembering that

T is the moment of force, and

d – shoulder length.

Let’s write the formulas:

T1 = F1 * d1;

T2 = F2 * d2.

In order for the balance to be fulfilled, the condition must be met: T1 = T2.

F1 * d1 = F2 * d2.

For d1 and d2 the values are:

d1 = 2 and d2 = 3.

F1 = (F2 * d2) / d1 = (20 * 3) / 2 = 30 N.

Answer: 30 N.