This is an illustration from Newton's Principia of his famous cannon thought experiment. It shows how a cannonball fired horizontally from a mountain top (assuming no air resistance) will orbit the Earth without falling to the ground if it is fired with sufficient speed. https://imgur.com/gallery/dzSLWaa
Now imagine an ice covered planet which is perfectly smooth, with no mountains or valleys. On the surface rests a curling stone of a given _weight_. If the curling stone is propelled horizontally with sufficient speed it will orbit the planet while sliding over the surface. At this velocity it will be in free fall so its weight will be effectively zero. The question is does the weight of the curling stone gradually increase as the horizontal velocity gradually decreases or does the curling stone resume its full weight for any velocity less than the orbital velocity? Harry
