In the most recent trailer for Thor: Ragnarok, it seems clear that Thor teams up with The Hulk, Loki, and Valkyrie—but for me, I’m mostly pumped up about seeing The Hulk again. Towards the end of the trailer, The Hulk is standing with the rest of The Revengers team (the name Thor comes up with on the spot).
But there’s something funny about this trailer: To me, it seems like The Hulk is much bigger in Thor: Ragnarok than in the previous Marvel movies. I’m what you might call an expert in Hulk heights; I’ve estimated his size before, like when I used it to get a value for his mass when looking at the force he exerts on the ground during a jump. In the Marvel Cinematic Universe (the Marvel movies that started with Iron Man in 2008 and continue through today), The Hulk has appeared three times with one more coming in the movie Thor: Ragnarok, out on October 25. So of course this means I need to go back and measure his size in each of the previous appearances—just to make sure.
How do you find the height of a fictional character? Yes, I am well aware that The Hulk is not real. However, that doesn’t stop me from trying to apply some cool physics to these make-believe characters. In short, the best way to measure The Hulk’s size is to find a frame where he’s standing next to some real object of known height. This object could be another character played by a real human (like Chris Hemsworth who plays Thor) or something else real like a car.
James Beacham looks for answers to the most important open questions of physics using the biggest science experiment ever mounted, CERN’s Large Hadron Collider. In this fun and accessible talk about how science happens, Beacham takes us on a journey through extra-spatial dimensions in search of undiscovered fundamental particles (and an explanation for the mysteries of gravity) and details the drive to keep exploring.
The MythBusters have been testing crazy myths since 2003—but now the show is coming to an end. Instead of despair, let’s look back at some of the great things we (myself included) have learned from the show.
Everyone Can Be a Scientist
The only MythBuster that had a technical degree was Grant Imahara, with B.S. in electrical engineering. Adam Savage and Jaime Hyneman have a background in special effects for movies. This is what makes them such epic builders.
But here is the awesome part—you don’t need a science degree to do science. In fact, I think that science is part of what makes us human (I adopted this from Chad Orzel). Science is just like other activities that make us human: art, music, and emoji (actually, just kidding about the emoji).
Even if you don’t know it, science is about building models (conceptual, mathematical, computational) and comparing them to real life. This is exactly what the MythBusters do in each episode. They usually start with a model—such as a conceptual model that says you can play Fruit Ninja in real life (yes, that can be a model). Next they compare this model to real data by building an elaborate setup of real-life Fruit Ninja.
Finally, this leads to one of three possible results:
- Busted: There was evidence collected that leads to belive that the model does not agree with real life.
- Plausible: There was not enough evidence to convincingly state if the model agrees with real life.
- Confirmed: There was convincing evidence that the model agrees with real life.
Why is there something rather than nothing? Why does so much interesting stuff exist in the universe? Particle physicist Harry Cliff works on the Large Hadron Collider at CERN, and he has some potentially bad news for people who seek answers to these questions. Despite the best efforts of scientists (and the help of the biggest machine on the planet), we may never be able to explain all the weird features of nature. Is this the end of physics? Learn more in this fascinating talk about the latest research into the secret structure of the universe.
Have you ever seen a child with a balloon? It’s fun to watch. Kids pay attention to the world around them: They know that when you let go of something, it falls. Balloons don’t follow these rules, and it’s that exception that makes balloons so fascinating.
But what about adults? We still love seeing things that don’t seem to follow our normal rules. Parade balloons seem to cheat physics in order to move through the sky. Of course, they aren’t cheating physics. It is because of physics that they are able to float.
Why Doesn’t the Balloon Fall?
There is indeed a force pulling down on these massive balloons. This gravitational force is proportional to the mass of the object. Both the outer material and the gas within have mass that results in a weight of perhaps 2,000 Newtons (450 pounds). Yet even with so great a downward force, the balloons stay aloft. There must be an upward force at work on the object. This is buoyancy force, and it is caused by a differential air pressure on the top and bottom of balloon.
You can think of the air as a bunch of balls bouncing around. When these air-balls hit a surface (like the side of a balloon), they bounce off. Since the ball changes momentum, it must be pushing against the balloon with some force. This force then depends on the number of air-balls that hit the surface as well as the speed and mass of the air-balls. But here’s the cool part. In order for all these air-balls to not just fall down on the ground, they must have more collisions in the upward direction than the downward direction. This means that as you go lower in the atmosphere, the density of air increases, resulting in greater pressure.
But how much does this air push on an object like a balloon? The easiest thing is to consider a block of air floating in air. Yes, that might seem silly but there is a reason for this. If there is no wind, that block of air in air should remain stationary. That means that the net force pushing on this air must be zero Newtons. Here is a diagram showing all the forces on this floating block of air.