The ideal mechanical advantage of a slope is given by the ratio between the output load, which is simply the weight of the object (), and the input force applied to move the object along the slope:
The energy conservation law states that the potential energy of the object when it reaches the final height h is equal to the work done to move the object along the distance of the slope , i.e.
From this we find
Therefore, we can substitute this into the formula of the ideal mechanical advantage and calculate its value:
The triangles ABC and A'B'C' are shown in the diagram below. The transformation is a reflection in the line . This is proved by the fact that the distance between each corner ABC to the mirror line equals to the distance between the mirror line to A'B'C'.
. This is proved by the fact that the distance between each corner ABC to the mirror line equals to the distance between the mirror line to A'B'C'.
