Station 2

In station 2, there was a scale on top of a track. I put a 20 N block on the scale when the scale was on flat ground. I then put a few books under one side of the track to put the track at a 10 degree angle. I put the 20 N block on now, the block showed up on the scale as only weighing 18.5 N. On a level track, there are only two forces working on the object, which is the gravitational force of the earth on the object and the normal force of the object on the earth. But when the angle is changed, another force is added. This is the frictional force of the track on the object. We know that the net force in both of these situations is zero, because the block is stationary.