If the world stopped turning.
Ever wonder what would happen if the world stopped turning? I know Alan Jackson thought about it but in a totally different way.
Since the Earth is roughly 24,000 miles around at the equator and rotates on its axis once per 24 hours. Objects at the equator at rest relative to the spinning earth have a 'resting' momentum of 1000 mile per hour. Object at the poles would have angular momentum. But it would be so low that observers might there might not notice the stop immediately.
Newton's first law of motion dictates that object at rest tend to stay at rest and objects in motion tend to stay in motion. Remember the magician's tablecloth trick? Only this time think of the table as being strapped to the top a speeding truck and instead of pulling the tablecloth out from under the plates, glasses and silverware, the magician slams on the brakes and plates, glasses and silverware fly forward in the direction of the truck's previous motion. So everything would continue under its previous momentum. The earth stops and everything zooms ahead at somewhere between 1000 mph and 0 mph (anywhere above 15 would be bad) People, cars, trains flying forward, spinning actually since friction at the bottom would slow the bottoms of everything initially. The atmosphere would continue moving until friction slowed it too, but at least it would be moving along with you. The water in the seas, lakes, and oceans would have tremendous momentum too. The surface would be scoured by the rushing waters. Wow and that's the part that lets me know it can never happen. God promised us the world never again be destroyed by water. Read Genesis.