According to what I've been taught, the distance-related redshift seen by Edwin Hubble is an artifact of an expanding Universe. That is, as light travels through space, space itself expands, redshifting the light (matter is embedded in space and does not itself expand but is instead carried...
Yes, as other pointed out, I made the mistake of effectively calculated with the car brakes locked. Since a wheel uses static friction, no energy is lost during normal movement. The number I got is a result of rolling resistance, wind resistance, incomplete battery discharge, energy losses in...
I think you've nailed it. My problem was thinking kinetic, but I should have realized that a wheel uses the coefficient of static friction. That is, by design of the wheel, we are simply "resting" on the surface in terms of practical calculations, although we are moving forward.
Thanks...
Hi guys,
Yesterday I sat down, and just for fun, decided to calculate the coefficient of kinetic friction for the all electric Ford Focus. I keep getting the wrong answer, and it is driving me crazy. Here are the facts.
Battery: 23 kWh.
Curb weight: 1,651 kg.
Maximum travel distance before a...
The infrared band is what I'm curious about. Also, my question was worded wrong...since liquid water has, on average, far more hydrogen bonds per molecule than water vapor, shouldn't there be an absorption difference? I would expect liquid water to absorb more strongly than vapor.
Water vapor exists at a higher energy state than liquid water...but does that make a difference in the absorption bands? In other words, are the absorption bands of vapor and liquid water identical?
Thanks!
Dave,
Thanks for all the links. I've thoroughly read each one, and I can say they proved a solid framework for beginning to understand Dynamo Theory. I had read the wiki article before, but the paper on the subject proved invaluable.
Based on what I've learned, the physics of DT can be...
Hi Dave,
My appologies, the thread was not meant to be marked undergraduate, but rather basic level. Thanks for pointing that out. Can you comment on the matter of currents?
I'm studying Dynamo Theory, and have just a few questions. Today's theory says that currents in the molten outer core of the Earth give rise to magnetic fields. Now it would seem that the theory does not mean "molten iron currents", since together that is an electrically neutral substance, but...
Thanks! Based on your post, I did a little digging, and it looks like Maxwell's equations have been used to develop the Biot-Savart Law. There is a special case for a moving charge.
Hi all,
This question has been bothering me for some time, so here it is.
I know that moving a charged particle, like an electron, generates a magnetic field. I know that moving electric charges in a circle (a loop of wire) generates a magnetic field. The question is, will a charge moving in a...
You are an excellent resource, thanks for running those calculations! The fact that errors grow larger as we near the beginning of the range of the 60 mA scale is particularly interesting. I suppose my last question is, how is the error curve generated? That we may never know. It seems curious...
It occurred to me that the inner workings of the fluke need current to operate, such as powering the LCD. This might cause a tiny voltage drop in the inner workings of the meter, and if this remained uncorrected, could show up in very small readings (where we are measuring tiny voltages). Of...
Yes, it was the same meter used for measuring both current and voltage. How does range changing for an ammeter work ... are different shunt resistors selected? Would range changing or a moving zero adjust be able to produce the effect shown, though? It appears to mimic the equation A - e-x ...
The first datapoint may very well be iffy, good point. Is it normal for meters to be oppositely calibrated ... that is, reading low on the voltage, and high on the current? I know the effect we're looking at must be generated by the meter, and it seems tied in with the amount of current...