**Equivalent force systems: Distributed loads**

**Replacing distributed loads by a resultant
load and resultant couple applied at a given point ***O ***:**

**Replacing a distributed load by single
resultant load:**

**Note: **Since the equation for *d *is
the same as that for determining the centroid of the
area under the *w(x) *curve, it follows that *F *must pass through
the centroid of the area under the curve *w(x).*