Here's a Question! - Which Hits the Floor First?
Two identical basketballs are rolled across a horizontal table. One is rolled slowly, and the other, quickly. Both basketballs reach the end of the table at the same time and fall to the floor. Which one hits the floor first?
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Joanna and Steve: Just science!
Joanna: Hi! I'm Joanna!
Steve: And I'm Steve!
Joanna: Here's a question for you...
Steve: Two identical basketballs are rolled across a horizontal table.
Joanna: One is rolled slowly, and the other, quickly.
Steve: Both basketballs reach the end of the table at the same time and fall to the floor.
Joanna: Which one hits the floor first?
The one that was rolled slowly?
Steve: The one that was rolled quickly?
Joanna: Do they both hit the floor at the same time?
Steve: Or, do they not hit the floor BECAUSE THERE IS NO FLOOR!
Joanna: Pause the video now if you'd like to think it over before we show you what happens.
If we ignore friction and air resistance, and if we assume the floor is level, then how fast the basketball is moving horizontally will have no impact on how long it takes to hit the floor.
Steve: The amount of time it takes for the basketball to hit the floor depends on how tall the table is, how strong gravity is, and how much, if any, vertical motion the basketball had to begin with. If all three of these things are the same for both basketballs, then the amount of time it takes them to hit the floor will also be the same.
Joanna: While our floor might be level, the Earth isn't. On larger scales, the horizontal speed does impact how long it takes something to hit the ground. Give something enough horizontal speed and it won't hit the ground at all. It'll be in orbit around the Earth.
Thanks for watching. I hope you'll join us again soon for another question!
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