# A balanced lever has two weights on it, the first with mass #6 kg # and the second with mass #7 kg#. If the first weight is # 4 m# from the fulcrum, how far is the second weight from the fulcrum?

##### 1 Answer

#### Explanation:

As we are determining the distance it does not matter what units of weight we use as long as they are consistent.

I am also going to demonstrate how to deal with the units of measurement. If you deal with 'Statics' to any extent then manipulating units is exceptionally important!

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If the moments do not match then it means that the system is in motion. We can use this fact to determine the moment arms needed to establish equilibrium.

A Moment is the number resulting from an applied force multiplied by its distance to a point of rotation ( actual or theoretical).

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Let clockwise moment be positive.

Let anticlockwise moments be negative

Then for equilibrium to exist

For this to be true then:

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To find