(How to make your own fake moon videos - or how to undo the fake studio videos)

Stop. Don’t say it. I know the moon landings were real, but I am just trying to have fun.

Some claim that the Apollo moon landings were faked in a studio. One way to make fake films would be to film astronauts and then slow the film down so it looks like they are on the moon. If this were the case, I could speed the videos back up to “normal” speed and see what they look like. After that, I will take normal videos and slow them down to make them look like they are on the moon.
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Tags: kinematics, gravity, video, fake, units

Can you believe it? Have you seen this video?


Are you thinking what I am thinking? WOW. How could these people not follow my rules for cool internet video. Once again, here they are:

1. Keep the camera stationary. This way I don’t have to keep moving the origin in the movie.
2. Don’t Zoom. Same reason, this video followed that rule.
3. Include a clear and obvious calibration object. A meter stick would work, or even a Kobe Bryant (I can look up his height). Maybe it could be a Ford F-150 that has a known length. Something!
4. Include the mass and height of all people involved.
5. Use high quality video.
6. Don’t talk about fight club - oh wait, wrong list.

Despite failure to follow all these rules, I have managed to analyze this video. Really when I saw it, I said “wow” - was that real? It looked real, but who would get shot up that high? (it is on break.com, so fake is a possibility).
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Tags: kinematics, video, energy

You see this all the time in textbooks:

This is often described as “the acceleration due to gravity”. Is this really the best thing to call this? No. A better name would be “the local gravitational field” and list it in units of:

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Tags: gravity, kinematics, forces

We have all seen the Kobe Bryant video of him jumping over an Aston Martin - this keeps coming up on the Internet. There has been vast discussions of whether this is real or fake. I will do my best to examine the evidence. In short (in case you don’t want to read the whole thing) Kobe can most likely really jump that high, it is possible that there was some perspective trickery involved. Here is the video in case you are brand new to the WWW:
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Tags: kinematics

Ok, I am trying to be quick with this, since it is current. Here is an awesome video of Kobe Bryant jumping over a pool with snakes in it (I found this on digg):


It looks so crazy, I wanted to do a quick analysis to see if this is feasible (well, I know it is not feasible for me). Let me just pull out one of my favorite tools - Tracker Video Analysis. Read More...

Tags: fake, kinematics, video

Here is a nice little (well not too short) quiz on the basics of high school level physics (with no math). Basically it is a true or false type quiz. Take it for fun:
Physics Savvy Quiz
I missed a couple of the questions (well, technically I missed three).

One question was about negative acceleration. I really don't like this because I think of acceleration as a vector:

In which case "negative" acceleration does not really make sense. If you are talking about components of acceleration, then you can have a negative component. It is possible to have a negative component of acceleration in the same direction as the component of velocity, so that would make the speed increase. I guess I am just sensitive about vectors. (really I am just making an excuse for why I missed that one).

The other one I missed was comparing milliliters and cubic centimeters. I never see milliliters and accidentally read it as millimeters. You can't compare millimeters and cm³, so I chose false. That is wrong.

The last one I missed is completely my fault. It was asking about the mass of a cloud. Really, just a lack of knowledge on my part.

Anyway, check out the quiz. Lots of fun. Really, I am just stalling because I have not finished my next project and I don't want to leave my site unupdated (I know thats not really a word).

Tags: kinematics

So, you knew I was going to make some mistakes on the physics of scooting - right? I don't think these mistakes are major and they don't take away from the main idea. Read More...

Tags: forces, kinematics, modeling, momentum

There you are, in your rolling chair. You need that extra pencil, it is just a few feet away but out of reach. For some reason, you don't want to touch your feet to the floor. How do you get that pencil? You scoot. Still don't get it? Here is an example:

Why do people scoot? I don't know. My kids do it too. When does a human learn to scoot? How does a scoot work? Really, I am just going to answer that last question, but the others are interesting also. Read More...

Tags: forces, kinematics, modeling, momentum

In case you never saw it, here is the part of the episode where the Mythbusters explode a water heater.

I started to analyze this previously, but it wasn't complete. Now I will finish what I started.

If you are curious, here are the "answers":
Time of flight = 11.8 seconds.
Max height = 167 meters = 548 feet
Speed on impact (ground) = 34 m/s = 76 mph (compared to 234 mph initially). Read More...

Tags: mythbusters, kinematics, video, air resistance

Suppose I want to have a lab activity with a dropping tennis ball. Do I need to worry about air resistance or can I assume there is none? This is a that was recently asked of me. Below is my answer: Read More...

Tags: forces, kinematics, numerical , computer, air resistance

Some time ago, I posted an analysis of the Ford F-150 commercial where the truck is shown to stop a landing C-123 Airplane. Apparently, this was quite popular and I received some useful and interesting feedback. From this, I have a few updates. Read More...

Tags: video, kinematics, forces, momentum

First, I am not really sure why Newton got to call this HIS law. Second, its not really a law. What happens if you don't obey this law? Would I go to physics jail? Ok, now for the good stuff. I am going to try to give a brief summary of Newton's 2nd law. Read More...

Tags: kinematics, momentum, forces

Aristotle: A constant force makes an object move at a constant speed.

Newton: A constant force makes an object move at a constant acceleration (changing velocity)
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Tags: forces, kinematics

Ford, why are you the way you are? Do you actually have people look at your commercials? Or do you just assume that you can say and show whatever you want and I will buy a truck? I am sorry, I shouldn't say that. I do enjoy analyzing your commercials - so, please continue.
Ford's latest F150 commercial shows a big thing dropping from a helicopter to the bed of an F150. The claim is that Ford is awesome. 30,000 lbs awesome. Let's check this out.
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Tags: video, modeling, momentum, forces, kinematics

Line Rider. Yes, its a game. Yes, I know its not real life. Nonetheless, I analyze what I see. How is the physics in line rider? Does it agree with Newtonian mechanics? What is the scale of the line rider? What other questions are there? What other questions are there? Read More...

Tags: forces, kinematics, momentum, energy

I am sure you have seen this commercial:

They say its a real demonstration, but it has seemed odd to me. (they also say this is a professional driver on a closed course and don't try this at home - damn! I was SO going to do that this weekend). Here is my analysis: Read More...

Tags: momentum, forces, kinematics