# A power estimate for heating a pool.

It is spring break, so we are at my parents house for a couple of days. The kids like it because there is a pool, a heated pool even. It really isn’t that cold outside, but yesterday the water measured at 62 oF. So, with some help from the kids, we cleaned out the pool…

# MythBusters: Crashing two moving cars, or one

I am so pumped up that MythBusters is back on. Not only do I like the show, but it offers so many blogging opportunities. Their latest show featured car crashing myths. One of the myths from the episode was a redo of the myth where two trucks crash head on simultaneously crushing a smaller car…

# Ruff Ruffman and Inertia Makes it Happen

Dear Ruff Ruffman, My kids really like your show. However, there is a problem. You promote it like it is science, but the content keeps having mistakes in it. Previously, I pointed out your mistake about in infrared thermometer (if can’t remember, you said the thermometer measures the temperature with a laser. In fact, the…

# LA LA LA LA LA – NY Times and the physics of football

People say I am picky. Ok, sometimes I am. But somebody has to stand up for what is right and just. Maybe I am that person. Please stop using the word force if you don’t know what it is. There. I said it. You can attack me now. It wasn’t just one thing that got…

# Physics of the Water Rocket

I said I would come back to this, and I am. I am a man of my word. Yesterday, I posted a link to a video of this really cool water rocket thingy. How does this work? What is the physics going on here? I think this can be best explained with the momentum principle.

# 90,000 KWhr for half a month

I just can’t pass this up. One of the chemistry majors had a complaint with the power company. After an unusually high previous power bill, they checked the electric meter half way through the month. The meter said they had used 90,000 kilowatt-hrs of electricity. That is a lot of energy. It is also a…

# Energy vs. Power. There is a difference

Here is an article from Wired.com that talks about a used cooking oil generator. It’s a really neat idea in that the oil is right there anyway. Here is my problem – from the article: A new garage-engineered generator burns the waste oil from restaurants’ deep fryers to generate electricity and hot water. Put 80…

# Water Bottle Rocket Guy

I saw this video posted on Physics and Physicists: It reminded me that I had at one point tried to analyze this. I had actually posted something about this on the first generation of my blog (which no longer exists). I have found the analysis, and here it is from the archives. Thanks ZZ for…

# Time Warp Samurai guy – waves of kinetic energy?

I am sure I have mentioned the Discovery show Time Warp before. The basic idea of the show is to find how many cool things they can look at with an ultra slow motion video camera (btw – this is on my christmas list). So, I have seen this Samurai guy on the show twice.…

# Basics: Collisions (Interactions between two objects)

Pre Reqs: momentum principle, forces,energy, vectors Really, there is not much new here. This is an introduction to objects that interact. To describe this, I will need to pull several different ideas together (that you have probably already looked at). Let me start with a simple case. Suppose I have two objects, maybe they are…