When you stand at rest on a floor, the number of vertical forces acting on you is?

Two forces.

Explanation:

If I am standing on the floor which is at rest then there will be two vertical forces act on me. One is in downward direction which is gravitational force and one is in upward direction which is normal to the gravitational force.

In the given below figure there is 2 forces mg in downward direction and normal force N in upward direction and these forces are equal.

N=mg

Here, m is the mass and g is acceleration due to gravity.

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