Fine, fine. My relationship with Rose is like a childhood playground swing.
The swing itself acts as a pendulum. By pushing a person---let's just say we're pushing Rose, shall we?---in the swing in time with the natural interval of the swing will make the swing go higher. The natural interval is the resonance frequency---normally associated with sound waves but actually part of an arc pattern found widely in nature and in many man-made devices. Sounds heard like metal, glass or wood are caused by brief resonant vibrations in the object. Light and other short wavelength electromagnetic radiations---we'll just call it ER for short…no, wait, can't call it ER, there's a telly program called that, isn't there? Maybe I could call it Electro R. No, that really sounds like an energy drink, don't you think?
Anyway, back to the swing! Where was I with the swing? Oh, right! Resonance frequency. Eventually, by using resonance frequency one would find themselves pushing the swing to the maximum amplitude, or that point before you swing over the bar and, according to some American television cartoons, turn inside-out.
So, the period of time from which Rose is pushed by someone---we'll say me---until she reaches the maximum amplitude is called the period of pendulum. That period can easily be equated to a sort of downtime between Rose and I, where things seem so much easier. Do you ever have times like that? Easier times?
So, the energy of the person pushing the swing is maximized when the pushes are at the resonance frequency, or just the right amount of pressure to keep it going without fouling up the arc by shoving or not trying hard enough. Some of the energy is canceled out by the inertial energy of the swing.
Now, considering we don’t want to push Rose inside-out, by the time we've reached the maximum amplitude, we'll slow down the pushes, shortening the arcs and increasing the energy that is cancelled out by the swing.
Rose on the swing makes her a physical pendulum. It's actually easier to express this if I write it. Do you have a piece of---oh, yes, thank you.
Where: I is the moment of inertia of the pendulum about the pivotal point, which would be where the ropes or chains attach to the top of the swing set.
L is the distance from the center of mass to the pivot point
And m is the mass of the pendulum, which would be Rose. Not that I think she's a mass of anything. She's…well, she's somewhat curvier than my average companion, but I'd hardly call her mass. More----what? Oh, right, staying on topic.
So, we don't want to push Rose beyond the point of maximum amplitude because no matter how many times I, myself, have gone over that bar, we don't know what could happen to Rose if she goes over. Am I right? I mean, the whole situation with her over the bar could mean disaster. If the arc isn't powerful enough---and considering the straightness of prior arcs, the possibility of it being powerful enough isn't nearly enough, is it?---then she won't make a full circle and will probably fall and be terribly hurt.
So, what we do is we get close to the maximum amplitude point and then slow down the pressure on the arcs. Bring her back down a bit, so she doesn't fly too far away and things don't get ridiculously out of hand.
Does that make sense?
I have a whole different explanation regarding a microwave if you---what? Out of time? Oh, all right. No, no, that's fine. Got to go pick up Rose and get back to swinging.
Muse: The Doctor (Ten)
Fandom: Doctor Who
Word Count: 664
Partner: (canon) banished_dame