# How long do you wait for a question to be answered?

I teach classes. I ask questions in class. I wait for answers. All faculty do this, so who cares. If you are in a class or teaching a class, how long do you wait for someone to answer your question? Well, I asked two questions of my class this week. 1. Estimate how long I…

# How about a massive catapult to replace the space shuttle

I recently saw a comment on a blog somewhere about putting satellites into space (I think it was from a post about a rocket that blew up). The poster suggested using a giant catapult to put things in space instead of rockets. Maybe he or she was kidding, or maybe not. But I have heard…

# Another MythBusters Tie in: zero-g in a plane

Maybe you can tell I am watching the MythBuster’s Moon Special. In the show, the MythBusters go in a plane to reproduce the gravitational forces on the moon. I previously went over this, so here is the link: [Tutorial on how gravity and weightlessness (zero-g) work](http://scienceblogs.com/dotphysics/2008/09/gravity-weightlessness-and-apparent-weight.php)

# Mythbusters Moon Stuff and Me

Clearly the MythBusters did this before I did (it’s just airing tonight though). I just wanted to say that I posted some videos of the Apollo “jump salute” video analysis and also sped it up to “Earth-like” accelerations. I then made a video of my daughter doing the same thing on Earth and slowed it…

# Heat. It’s a four letter word

Heat. You have heard it before. You have used it. I have even used it. Do we need this word? No. Is this a useful word? No. Let me start with the definition as usually stated in a physics type text: (this is from [dictionary.com](http://dictionary.reference.com/browse/heat)) *heat:* a nonmechanical energy transfer with reference to a temperature…

# The Iron Cross – or: Why is Gymnastics so Darn Difficult?

I know the olympics are basically over. Really, I should have posted this earlier. Anyway, the gymnastics feat that always impresses me is the Iron Cross (I think that is what it is called). I know you have seen this, but here is a picture from wikipedia: ![Example 2ofironcross](http://scienceblogs.com/dotphysics/wp-content/uploads/2008/08/example-2ofironcross.jpg) (http://en.wikipedia.org/wiki/Rings_(gymnastics)) Why is this so impressive?…

# ARRRGGGGG RapidWeaver, why do you hate me?

Dear RapidWeaver, What did I do to you? I like you, I really do – but this is why we broke up. It’s not you, it’s me. No wait, it’s you. I am looking back through my old dotphys posts and most of my introductions are GONE. I was starting to think I was crazy…

# Status of Pluto – Zombie Feynman Replies

I can’t believe there is still all this talk about what to call Pluto. Can’t we just move on? In an effort to help, I have summoned the Zombie Feynman to get his words on the subject. This is what he said:

# Moving my blog

As you may or may not have noticed, I have been using RapidWeaver for my blogging posts. (if you don’t know what that is, it doesn’t matter) Anyway, I think my stuff was getting a little too big for that software. It was a great place to start, but it is time to move to…