Wibbly Wobbly Timey Wimey Physics

This is really exciting! In my last blog post I talked about how it would be completely impossible for the T.A.R.D.I.S. to land on Earth's surface without so much as denting it. Well, one of the most recent episodes of the show the Doctor actually explained why the T.A.R.D.I.S. CAN land on Earth without even scratching the surface of the planet. Naturally, it's time lord science and probably not really possible in real life.

In the episode the Doctor says "Clara, I need you to pick up the T.A.R.D.I.S.. Carefully. It should be possible. I've adjusted the relative gravity." She responds "You mean you've made it lighter." After which the Doctor says " Clara, it's always lighter. If the T.A.R.D.I.S.were to land with its true weight, it would fracture the surface of the Earth."

I should mention, the T.A.R.D.I.S. is not full sized when the Doctor asks Clara to pick it up (that would be absurd). It's been shrunk! It looks a little something like this:

But anyway, this is the answer to my question from the previous blog post. Some how the T.A.R.D.I.S. is able to manipulate its own "relative gravity" which means the T.A.R.D.I.S. is not being acted on by the full force Earth's gravitational field. Rather, the T.A.R.D.I.S. is being acted on by a minuscule gravitational force relative to the Earth's actual gravitational pull. If the T.A.R.D.I.S. were not able to manipulate its "relative gravity" than the full weight of the entire dimension on the inside of the T.A.R.D.I.S. would be acting on Earth's surface and it would do some serious damage. Now, I do not believe this is possible on Earth since gravity is constant everywhere on the surface of Earth. Acceleration due to gravity is always 9.81 m/s² . Changing how aerodynamic the object is can change the acceleration of the object, like feather versus a pebble, but it will still feel the same force of gravity on the surface of the planet. The T.A.R.D.I.S. would- in theory- weigh so much that it could fracture the Earth's surface just by sitting on it. Not to mention the Doctor is changing the gravity acting on that T.A.R.D.I.S. without changing its shape or any at all. I can be sure how he does it, but I do know that we probably do not have the technology to emulate that effect.

I still can't get over this.

And this:

Meanwhile I'm just like:

Anyway, that is about all. Thanks for stopping by!

In this episode, the Tenth Doctor is on-board an intergalactic cruise ship modeled after the Titanic (yeah you would think they would've known better) which has traveled from a distant planet to observe the Earth holiday of Christmas. That's not what I am here to talk about though. When the ship gets hit by meteors, the compartment where the T.A.R.D.I.S. (time and relative dimension in space)- which is the Doctor's time-travelling spaceship- was being kept gets destroyed and the spaceship gets set adrift. The T.A.R.D.I.S. has been referenced numerous times as being bigger on the inside, and the interior has been likened its own dimension. Which brings me to my point. When he sees the T.A.R.D.I.S., the Tenth Doctor says "...once it's set adrift, it's programmed to lock onto the nearest centre of gravity, and that would be the Earth." And that is all well and good. But this is not.

This spaceship has just fallen from orbit to Earth and yet its wooden exterior is untouched and the ground underneath it is perfectly flat. Impossible. The Tenth Doctor said that the T.A.R.D.I.S. had locked on to Earth's center of gravity, meaning that it was being acted on Earth gravitational field. The T.A.R.D.I.S. is bigger on the inside, so if all that mass is accounted for, the force due to gravity (F_g=(mass_object)(acceleration due to gravity)) would be immense. That kind of force would create an enormous crater. And the wooden exterior should have caught fire during the decent as it entered Earth's atmosphere due to the friction created when moving from the empty vacuum of space into an atmosphere. Yet, the T.A.R.D.I.S. is unharmed. If the T.A.R.D.I.S. has no calculable mass, then Earth's gravitational field could not act on. But it is impossible to have no mass. And if the T.A.R.D.I.S.'s mass was only that of its interior it still should have caught fire upon entering Earth's atmosphere and it still should have shown some indication of hitting the ground. Simply put, there is no way for the T.A.R.D.I.S. to have landed without showing some sign of having hit the Earth's surface, there should have been a crater. So how do we explain this? Well, there is an easy explanation, just ask the Doctor.

Yeah, Time Lord science does't follow Earth's rules. That's the best I can give you. If you have read this and have a theory though I would love hear it, just put it in the comments.

Ok, now the fun part. I couldn't resist this. The alien tour guide in the episode is supposed to know all about Earth Culture and Christmas, but he has no clue what he's talking about and it is fantastic. Observe:

To which one can only respond:

Thought anyone reading this could use a laugh. That's all for now, stay tuned!

So in the third episode of the second season of Doctor Who, the Tenth Doctor had a brief stint as a physics teacher. To clarify, the man with the glasses is the Tenth Doctor, not be confused with the Eleventh Doctor who was in the last post.

Anyways, he asks the class some questions to test their knowledge. One question was this: "I coil up a thin piece of nichrome wire and place it in a glass of water, then I turn on the electricity and measure to see if the water temperature's affected.

My question is this - how do I measure the electrical power going into the coil?"

The answer is surprisingly simple, just ask Milo.

He responds that power can be measured "...using an ammeter and a voltmeter." But how exactly is that? You probably already know but I'm going to explain it anyway. The ammeter measures for current and the voltmeter measures for- you guessed it- voltage. Electrical power is equal to current times voltage (P=IV). If you measure the voltage and current going through the wire, you can calculate the electrical power the system is generating.

If you wanted the energy dissipated by the system, the electrical energy equals power times time. That means you would need a time interval for this to be occurring on (like 2 minutes or something like that). Eventually this could be used to find the energy transferred to the water and after that the temperature of the water after the system has acted on the it

over that time.

So to recap:

(Yes, this is my icon and now it has been explained!)

All of these gifs are from the actual episode as well, I haven't edited any of them. This was a pretty basic physics question, but important none the less.

A quick reiteration for anyone reading this that doesn't know what Doctor Who is: it's basically a show about a time-travelling alien and his human companions (you really should watch if you haven't). My weekly blog posts are going to be about the physics of Doctor Who from episodes past and present. I'm not going to get into the physics of time travel just yet though.

I'm going to start with this:

So there is an average, run of the mill human being floating in space with nothing but her pajamas on. Except, physically that doesn't make any sense. In order for Amy (that's her name by way, and the man holding her foot is the Doctor- the alien who time travels) to be able to live in space there would need to an atmosphere, so that she had the oxygen necessary to breath, and there isn't one in space. Space is a vacuum which means there is no atmosphere and therefore Amy would not have air to breath and would be unable to live while floating in space like she is and yet she does. How is this explained then? On the show, the Doctor tells Amy that the T.A.R.D.I.S. (his time machine, the blue box) created an atmospheric shell, effectively creating a bubble around itself so that living beings can breath and thus Amy could breath. I don't believe this something that it is possible by today's standards but then again this show isn't always set in today's time. This would be an example of the writer cleverly working around the fact that 75% of what happens on the show defies at least some physics concept. Ok, that would be it for now, but I'm working more so stay tuned!

Hello! If you are reading this then you've found your way to my physics blog.

To be honest, I did not expect to be doing this sort of a thing when I chose to take AP Physics C, but I'm not complaining either.

A little about me first then. I believe I am fairly strong intellectually, particularly with math and science because I find it much more interesting than most other subjects. I hoping that AP Physics C will help me improve my calculus skills though, as the concepts are new to me. Having taken previous physics courses (what used be known as AP Physics C I took great interest in optics. I'm hoping to study Imaging Science in college, which is essentially the study of an imaging captured and perceived.

So now why AP Physics C? Well, having interned at the Rochester Institute of Technology's College of Imaging Science, I learned that physics and calculus are quite important for an Imaging Science major. For that purpose, I choose to take AP Physics C, hoping to improve my knowledge of physics and prepare myself for college. I'm really looking forward to the lab experience and I'm actually excited that we have such a small class size because we have all already started helping and working with one another on classwork and labs. I'm still a little anxious about having to teach myself individually without the help a lot of guided class lectures but I also think it will be a great lesson to learn as I move towards college.

I'd like to explain real quick what my blog is all about. Each of my posts is going to be based on an episode of Doctor Who. Haven't watched it? Here's a quick synopsis: its TV show about an time-travelling alien and his human companions and it recently had its 50th anniversary special. There's a lot of physics concepts that are ignored or worked around on the show so that's what I'm going to talk about. Each post will center around an episode, either a new one or a past one.

And let's hope I can come up some more interesting post titles...sorry about that. Oh and all the images used here are from Doctor Who.

Now...