Which Will Hit The Bottom First When Feathers And A Bowling Ball Are Released At The Same Time In A Vacuum?

A simple experiment gets a massive upgrade.

It’s a simple experiment you probably saw for the first time in elementary school: a feather and penny are dropped into a tube, with onlookers asked to guess which one will drop first.


"The penny!" the children unanimously cry, because pennies weigh more than feathers. As expected, the coin easily outpaces the feather as it hits the ground. 

Next, the science teacher pumps the air out of the tube, creating a vacuum. Again, the teacher asks which will fall first. This time, the answers aren't so clear. When the race is on, the penny and the feather hit the the bottom at the same time. Same penny and same feather, different outcome. 

But why? 

In the second trial, the vacuum removed air resistance from the equation, allowing both objects to be affected only by gravity.  Acceleration due to gravity is constant, regardless of the mass of the object.

Brian Cox, a particle physicist at the University of Manchester, decided to scale up the experiment just a smidgen. On an episode of Human Universe, Cox ventures to NASA's Space Power Facility in Cleveland, Ohio in order to replicate the experiment with a bowling ball and large feathers.

The facility was designed to replicate the vacuum of space, in order to test out spacecraft during development. In the video, however, it's used to test out one of the most fundamental forces of the Universe.

It is generally believed that Galileo first had the idea that gravity was a constant force in 1589 when he dropped a cannonball and musketball from the top of the Leaning Tower of Pisa in Italy. Though the two objects had greatly different masses, they hit the ground at the same time. Modern incarnations of the experiment use a feather to demonstrate the effect of air resistance, and help show the true effect of gravity.

Watch the video to see this simply amazing experiment for yourself:

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