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The Formidable Physics of Spider-Man's Water Monster

I'll be honest. I really have no idea what's happening in this trailer for Spider-Man: Far From Home. But no matter, I'm still super pumped. You know what happens when I get excited? Yup, I start doing physics calculations. So, let's look at one part of this trailer and try to figure some stuff out.

First some quick background. In the comic books, Mysterio is a villain who has powers based on special effects. Many of the things he does are just tricks. In the movie version this might be different—but I just thought I should point that out. Now for the scene: We see Peter Parker in what appears to be Venice with water and stuff. Then out of the water comes this giant water monster. Is it real? Is it just a special effect? Who knows. But the water monster is where the physics comes into play.

Suppose Mysterio has some way of forming a monster from the water. How much power would this take? That is what I'm going to estimate.

Let me start with some water monster estimations from the trailer. Also, I should be clear—I don't know what that thing actually is. It could be something from Mysterio, it could be an illusion, or it could be another villain such as Hydro-Man. It could be. But I'm assuming that Mysterio does something to actually move the water in that way.

Here are my estimates:

  • The creature is made from water with an approximate cylindrical shape.
  • This water monster cylinder has a height of 7 meters with a diameter of 2 meters. I get this from seeing the water monster near a building—about 2.5 stories tall.
  • The monster forms in about 3 seconds. Yes, this is a rough estimate since we don't see the whole monster growing out of water.

Now for some physics. The first idea to consider is energy. If you take a book and lift it from the floor to a table, you have to add energy to this book. In this case, it would be gravitational potential energy. On the surface of the Earth, the change in gravitational potential depends on three things: the local gravitational field (g), the mass of the object (m), and the change in height (y) of the object. As an equation, it would look like this:

It's important to remember that only the change in potential matters since the "zero point" could be set to any location. No matter where you put the zero potential, the change in potential energy for a particular motion will be the same. For a quick example, let's go back to lifting a book off the ground. Let's say the book has a mass of 1 kilogram and the table is 1 meter above the floor. If I use a gravitational field of 10 newtons per kilogram (it's actually about 9.8 N/kg), the change in potential energy would be 10 joules. This is a nice problem because you can actually lift a book like that and get a feeling for the value of a joule—the unit for energy.

Now for the second physics idea to use on Mysterio's water monster—power. Power is the time rate of change of energy. It's a measure of how fast you change the energy of something. Let's go back to the book on the floor. If you put it on the table it takes 10 joules of energy. However, if you do it really quickly it will require more power than if you do it slowly.

Power is defined as:

If the change in energy is measured in joules and the change in time is in seconds, the power would be in watts. But that's enough physics. Let's get back to the water monster. Here you can see we need to calculate two things. First, how much energy would it take to lift the water up to form that monster? This would be just like lifting a book off the floor except that it's a water monster. Second, using the time to lift the water, I can calculate the power.

Of course the water monster still stays on top of the water. So how do you calculate the mass and height for the change in gravitational potential energy? It really doesn't matter about the bottom or top of the water monster. What matters is the height of the center of mass. If I assume the monster has the shape of a cylinder (with uniform density), the center of mass will be halfway up the cylinder. It's a good thing I already estimated this height. That height is the change in y for the change in gravitational potential energy.

What about the mass? If the water monster is made of water, the density of the monster will be the same as the density of water with a value of 1,000 kilograms per cubic meter. This means I just need the volume of the cylinder to multiply by the density to get the mass.

I can use that to get the change in energy and then divide by the time to get the power. Let's do this in Python so that you can change the values in case you think I'm crazy. Notice how nice it can be to just calculate parts of your equation before putting it all together. Yes, you should be using Python for your calculator. Just click the Play button to run the code.

The final power is around 250,000 watts. Is that a large power? As a comparison, your laptop computer uses about 30 to 60 watts. Maybe it would be better to convert this to another unit for power—the horsepower. One horsepower (the unit, not the actual horse) is 745 watts. This means the Mysterio monster would take 335 horsepower to lift up that quickly. Is that possible? I guess if you have a pretty beefy sports car or truck you could do it. It's not crazy out of line for this water monster. Maybe Mysterio really does lift up the water for this special effect.

Yes. I know. It's just a movie. That should never stop anyone from having some fun with physics though.

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