Here's why:
* Normal Force: This is the force exerted by a surface perpendicular to the object in contact with it. It's a reaction force to the object's weight pressing down on the surface.
* Scales and Normal Force: When you stand on a scale, your weight (force due to gravity) pushes down on the scale platform. The scale's platform then exerts an equal and opposite force (the normal force) back up on you. This is what the scale measures.
Important Note: The scale reading is not the weight itself but rather the magnitude of the normal force, which is equal to the object's weight when the object is at rest on a horizontal surface.
