energy

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Tag archives for energy

What if everyone jumped?

Might as well jump. Jump. Go ahead, jump. – Van Halen Suppose everyone in the world got together and jumped. Would the Earth move? Yes. Would it be noticeable? Time for a calculation. Note: I am almost certain that I have done this before, but I can’t find where. Starting assumptions. 7 billion people. Average…

Why would I think that?

So suppose you saw something that looked like this: This is a ball shot out of a shooter device. Well, it is a vypthon animation of a ball. What would you do if you came to see this video? If I had not made it, I would say it is an unrealistic video. It does…

Grades are in. So, let me just say a couple of trends that I saw on the physical science final exam. Gravity on the moon I asked the question: “why is the gravitational force on an astronaut less on the moon than on Earth?” The simplest answer is that the gravitational field on the moon…

I already mentioned the MythBusters’ crashing two cars episode where they correctly doubled the speed of a pendulum type object. Overall, this was a very visual (although expensive) demo. There was one part that left a sour taste in my mouth – the final explanation from the narrator. First, they showed this. And then they…

Repost Compost for Earth Day

I wasn’t paying attention. Earth Day is today. If I would have thought of this before, I could have done something awesome. Instead, here are some reposts related to the Earth and energy. They have been sitting for a while in my post-compost, so they are nice and smelly. Most of these deal with Earth-type…

Physics Tips for Media

You probably already know how I feel about the “media” and their physics explanations (see attacks). Let me summarize the problem. There are a whole bunch of cool shows on tv that deal with sciency stuff – that is good. These shows then try to teach some science along with their demos and explosions and…

MythBusters and physics terms

In the last episode of MythBusters, they tried to reproduce the following experiment. Suppose you are driving in a car at 60 mph and you shoot a ball backwards at 60 mph (with respect to the car). Will the ball just drop (with respect to the ground)? Actually, it is a cool demo – I…

Sport Science: Pulling and Power

I would like to continue my attack on the show Sport Science – ESPN. In this short episode, they are comparing the power of NFL player Marshawn Lynch with that of a truck. You can watch it here if you would like. There are two things that are not quite right with this episode, first,…

Which wastes more fuel? (and thus produces more carbon dioxide). This is a difficult to question to answer for a variety of reasons. The main reason is that a speed change from 71 mph to 70 mph is different than a reduction from 56 to 55 mph. First, let me be clear that the question…

Energy in an exploding water heater

The more I think about the last MythBusters’ exploding water heater, the more cool things I see. How about I look at the energy of the explosion. There are three things I can look at: How much energy went into the water heater from the electric source? How much kinetic energy did the water heater…