FN Normal force Perpendicular (i.e. normal) to the surface. Equal to whatever force is needed to prevent the object from falling through the floor. Use the FBD recipe to find FN . FT Tension In direction of the rope or string (away from the object).
The Mesosphere is the layer of the atmosphere that protects the Earth from meteoroids. It is also the coldest layer of the atmosphere. Below it is the stratosphere and above it is the thermosphere.
