The Rebel

Thanks for the website. I've been meaning to try out creating music in 5.1 or above. I've got a couple of multitrackers but have never had the know how of accessing rear speakers for example, and direct a channel to that speaker. I think I'll check out these bits of software. Does anyone know if my SPDIF output (alongside the standard stereo output) is appropriate for multichannel outputting via 5.1. speaker setups; or will I need a dedicated multi-channel sound card??

I think the gun is confusing the idea a bit. The gun doesn't really accelerate a bullet in the same terms as this topic is on. A gun works on collisions and the transfer of collision energies. A ball bearing on a slope works on potential energy (GPE) accelerating towards Kinetic Energy. Correct me if I'm wrong as I struggled visualing these angles during mechanics, however, lets consider the ramp above. Gravity acts straight down, and as a result there is a reaction force perpendicular to the incline. The formula being R = g cos (angle). If we consider the horizontal component of this reaction, we find that there is an acceleration (we're assuming the friction is zero) against the surface. F = R sin (angle) Therefore F = R sin (angle) = g cos (angle) sin (angle), which gives a parabolic when plotted between 0 and 90. Showing how the force is at a maximum when the ramp is at 45 degrees and reduces in either direction. As the ball leaves the incline, the reaction is equal to gravity, i.e. there is no horizontal component, it is down to friction to slow the ball down. However the initial velocity as the ball reaches the end of the incline, that determines the stopping distance would already have been decided on by sqrt(2*acceleration*distance)

What type of switches are they? Normally open or normally closed, and are they latching. If you only use push switches, you'd have to start adding relays in. If the switches are latching you could probably get away with a DPDT relay, if not then a TPDT (i.e. triple pole) relay. Otherwise, and if the switches are of the same type, you'll need two relays. Depends whats available.

My understanding of it is that horsepower is all about work, and how much energy is used for a particular job, e.g. torqueing something up, or dragging something, etc. It's equivalent to force x distance. Brake Horse Power is a measure of capability. I think its based on the amount of horses need to do the same work as the engine in the same time. To measure BHP we basically take an engine up to full speed, add some resistance (thus lowering the speed of the engine by torque), and equate the energy the engine is giving off by subtracting the work used on the load to the measurement at the opposite end. One example would be to wrap a rope around a pulley being driven by an engine. One end would be trying to lift a weight the other would be measuring the weight. The difference between the two shows the work done by the energy. Another is to have a clamp on a pulley driven by an engine under test, which is connected to some weights, the height the weights travel at a certain engine speed ( a bit like the biting point in the car, when the car starts to lift from the front), gives a BHP value. Today they use a dynamo either directly connected via a flywheel or using "rolling roads" and add in transmission losses, to find the power given by the engine in BHP.

Is this a stepper motor or a power motor. Difficult to tell whats going on in this pics, I think its simply that electromagnets are being energised in succestion, causing the rotating part to constantly align itself, and effecting spin.

I should imagine this would be used for government secrets . . . I could do with the memory pill though. If something clicks it stays for time, but my recall . . . hopeless. Lucky to remember what I had for dinner yesterday.

Hmmm tricky one ... The only thing I can think of is to substitue the ln x such that x = e^v, which leads to int: v^2.e^v and finish off by using integration by parts. Don't take my word for it though. I ain't tried it. EDIT: should've read v^1/2.e^v but still not sure of this route.

I have to admit I have wondered about the possibility of modelling traffic, although I'm not sure if this is the line you're going down. For example would it be possible to think of roads like electronic circuits where each one would have a different average speed, average rate of flow. If three roads were connected in different ways, e.g. traffic lights, give way, roundabouts, would it be possible to map a prediction for tha behaviour of the thirs road from the two others. How would verifying components (junctions, etc.) change the flow. Perhaps there is a traffic modelling program already out there?

I understood that eletricity is undefinable, is it flow of charge, is it PD, stored charge, a flow of energy??? Hence we can not describe how it behaves.

To be honest I don't know anything about UCL, so I wouldn't know. I can only suggest looking up some sites of the internet and seeing what the reviews are like.

Probably loads of ways, depending what you got around you, the characteristics of the pressure sensor, and what circuitry is already in place (i.e. the guage). The easiest way is probably to put the pressure into part of a potential divider that feeds a transistor (BC109 will do). This in turn will act as part of a second pontential divider which will feed a second BC109 (through a 1k bias resistor) for the warning light. You could also put it into a wheatstone bridge with an op-amp. The op-amp doesn't have to be anything special if its just a warning light. Or you could use the resistance as part of an opamp circuit.

I'm liking these questions you're giving cos it gives me the chance to refresh my memory on all the stuff I used to do at college on further maths. The answer is basically (0.5x * (1-x^2)^0.5) + 0.5arcsin(x) It's actually a question I did in one of my assignments, so I got the equations for it too. Unfortunately, until I either got my math editor on word working, or learn the maths codes on here a bit better, it would take too long to write. But it involves integration by substitution, where you substitute x for sin v. You also need to know a couple of trig identities like: cos2x = (cosx)^2-1 and sin2x = 2sinxcosx. EDIT: I've just found a generic formula in one of my old calculus books as follows: int : SQRT(a^2-x^2) = 0.5x * SQRT(a^2-x^2) + 0.5a^2arcsin(x/a) Notice that if we have x equal to the radius (a), the 1st part cancels, leaving 0.5a^2arcsin(a'/a). If we then take the values of a' = -r and r we get: 0.5a^2arcsin(a/a) - 0.5a^2arcsin(-a/a) =0.5a^2 * pi - 0.5a^2 * -pi = pi * a^2

I can't see mathematical formulas anymore. All I see is math in brackets and /math in brackets with all the text/codes in between. They aren't coming out in the proper script. This goes for ALL posts that have used this code that i read. Is anyone else having this problem. Do you know how I can see them again?

It was simply a little bit of algebra with simultaneous equations. You already had the formula y=ax^2+b^x+c. By imaging two points we had the formulae: y1 = ax1^2 + bx1 + c and y2 = ax2^2 + bx2 + c. We can cancel c by subtracting y1 from y2. To give us a formula with variables a and b. y2-y1 = a(x2^2-x1^2) + b(x2-x1) Because you stated a=1' date=' we can rearrange for b in terms of x1, y1, x2 and y2. That's how I came up with the formula. [b']b = (y2-y1 - (x2^2-x1^2)) / (x2-x1)[/b] As for c. . . Once you have found what b is you simply put the value of b into the formula along with say x1 and y1 to find c. e.g. y1 = x1^2 + bx1 + c => c = y1 - x1^2 - bx1

In that case for [math](x_1, y_1)[/math] and [math](x_2, y_2)[/math], [math]y_2-y_1 = x_2^2-x_1^2 + b(x_2-x_1)[/math] which equates to [math](y_2-y_1 - x_2^2-x_1^2) / (x_2-x_1) = b[/math] Then once b is found plug in the values to find c

Google says its called a metalloid line http://www.madsci.org/posts/archives/jan99/915517377.Ch.r.html

Wouldn't you need three points to find three variables. For example the two points (0, 12) & (2, 32) satisfy [math]x^2+8x+12[/math] and also [math]3x^2+4x+12[/math] at least. Two points wouldn't even tell which way up the quadratic was (i.e. the x^2 coefficient)

There's a very good reason (I thought) for the name The Rebel, maybe one day I'll properly introduce myself on the "official introduce yourself" thread.

I very much doubt this is possible to put into a general formula. As functions become more complex' date=' there could produce any number of intersects between each function and the axis, in any four of the quandrants. Therefore generating any number of shapes to find the area of. The example of [math']x^{3}-x^{2}[/math] is easy enough because of its simple shape. Then take an example of circle [math]x^{2}+y^{2}=1[/math] placed on top of a high amplitude, high frequency sine curve. There could be many different areas formed, some "in the air" away from the axis within regions of areas that sit on the axis. I think with any integral, the functions have to be visualised before the calculations can take place.

This could be argued though. Over a distance of different mediums in varying environments, light does bend and change speed too. Only by constraining everything to a vacuum and/or considering light a very small scale between each change in a photon within a singular medium do we consider it to be straight. But then, if we broke all "travel" or "movement" down to infinite steps, would it not all be travelling in straight lines???

I would split the area into two shapes resting against the x-axis, and breaking by a line parallel to the y-axis at the intersecting point, and add the totals.