# Mechanics: Inclined Plane on a weighing machine

So there was a this question I have been wondering about mechanics. Consider an inclined plane of angle thetha with mass $M$ and an object sliding on it of mass $m$.The inclined plane is in a weighing machine.What weight will the machine give while the mass $m$ is sliding how it compares to when it isn't sliding.

I was thinking about the acceleration of the center of mass and the external forces,then clear for the Normal force of the mass $M$ but I have trouble with the vector form of acceleration cause it isn´t only in the y direction so how can it equal the external forces that are only in $y$ ($F=ma$)? Or is there another way to get the Normal Force? First I thought is equal to the weight as normal but I don't think it's that easy. So thanks for the help and ideas.

The wedge has no component of acceleration in the vertical direction, so this weighs $Mg$. The object sliding down the wedge has a component of acceleration $a$ in the vertical downward direction; its weight is $m(g-a)$. Note that if $a=g$ then this object is in free fall so it weighs nothing.