Galileo the Scientific Parrot
Okay, so we're at the University of Sydney to experiment with Dr. Phil's dead bird. He's a famous scientist, this guy. He helped us out back in, uh, the 16th century, I think. Uh, the 17th century, isn't it? 17th century, 1600s.
Thank you! Galileo was, uh, was discussing gravity. A lot of people, of course, thought that different things fell at different rates. But Galileo said, "No, no, no, no, no! Gravity is the same for all bodies, no matter how heavy or light."
Um, so we're going to prove that right now, aren't we? Okay, let's give it a shot. Yeah, so, um, young, uh, Galileo here is going to lend us a feather. The feather's very light, but it's still going to fall at the same acceleration as this coin made of metal.
So you're telling me they're going to accelerate together towards the ground? That's right! And you know, I don't believe you. How could you? I'm a scientist!
All right, so let's do the experiment. Let's see what happens. Yeah, one, two, three... That's actually going upwards!
All right, so what was happening there? Obviously, they didn't accelerate down at the same rate. Well, maybe there's some other factors going on here. What do you reckon?
Maybe! Or maybe it's, uh, it's the dead bird's fault! Maybe it's the dead bird's fault; he was blowing up, blowing its air. Maybe we need to get rid of the air. What do you reckon?
Okay, let's get rid of the air and see what happens. As it happens, we've got a vacuum pump here. Okay, so if we put this feather and this coin in here, seal it up, then we can pump all the air out.
All right, let's do it! So we're sucking all the air out now, coming out of the pipe, down the tube, out of here, through the air. So, so, uh, we're really getting rid of most of the air, so there'll be no wind resistance as the feather falls this time.
It's kind of like a vacuum cleaner, but it really sucks! All right, so, uh, let's try it out. Let's see if, uh, they accelerate at the same rate now. Right? You ready for this?
Yep! One, two, three... Wow! They did fall at the same rate!