Using Reason's Transpose, Quantize, and Velocity Function [aboutcomputer99.blogspot.com]

Using Reason's Transpose, Quantize, and Velocity Function [aboutcomputer99.blogspot.com]

Question by akash: How is the velocity of a satellite controlled when moving in elliptical orbit? The velocity of a satellite at perigee (10.15 km/s) decreases to a min. 1.6 km/s at apogee during its journey along an elliptical orbit. Is this velocity reduction done forcefully using computer measuring the height of satellite at every moment or it happens naturally by gravitational force and momentum ? Best answer for How is the velocity of a satellite controlled when moving in elliptical orbit?:

Answer by Linuxiac
Yes, all due to the laws of physics!

Answer by Ubi
Kepler's Laws of planetary motion are quite interesting... check them out (particularly his 2nd law for your question). The velocity is usually not controlled in a satellite, it is left alone once it is in orbit. Since an orbiting object has to sweep equal areas in equal time (by Kepler's 2nd law), the object must move faster near perigee since the area slices are smaller than those when near apogee. See the animation at the linked site.

Answer by gjmb1960
the last one.

Answer by luv_hanoz
its physics... by keplar's 2nd law of satellite motion " the body revolvin around d parent body spans equal areas, for the same intervals of time, anywhre in its orbit" hence for this 2 b true...its speed is max at perigee and min at apogee make a diagram...n then c..u'l b able 2 undrstand better

Answer by joe_ska
In addition to Kepler's Laws as the others have suggested, another way to get an understanding is the conservation of mechanical energy. As the satellite moves through its orbit it trades potential energy for kinetic energy. That is one explanation as to why it is moving fastest at the perigee and slowest at apogee. The total mechanical energy remains constant. Conservation of angular momentum also provides some insight, but maybe not as clearly. The total angular momentum is also constant and is equal to the vector cross product of the position vector and the velocity vector. So as the magnitude of the position (the altitude) increases that of the velocity decreases, and vice versa. This also explains why the satellite stays in its orbital plane, though that may even be less clear.

Answer by David in Kenai
The satellite is in a constant state of free-fall, controlled by the planet's gravity. No satellite carries enough fuel to accelerate and decelerate that much even for one orbit. Example: Throw a ball in the air, almost vertically. It starts fast, is slowed near the top of it's arc (when all its speed it horizontal) and then speeds up again at the bottom of its fall. Similarly, the satellite accelerates from its apogee until it is going fastest at closest approach (perigee) and slows again until it reaches apogee again. Satellites do have small thrusters to change their orbits slightly. But such "repositioning" or increasing a decaying orbit can only be done a finite number of times.

[velocity computers]

Welcome to another Good e-Reader Comparison Video! Today we take a comprehensive look at the newest tablets from Elocity and Velocity Micro! We compare hardware, software, video playback, apps, ebook page turn speed and much more!

aboutcomputer99.blogspot.com Elocity A7 and Velocity Micro Cruz Tablet T301 Comparison

The good: The Velocity Micro Vector Campus Edition is one of the fastest general-purpose PCs in its price range. The bad: The focus on CPU speed means this system doesn't have the most well-rounded feature set. The bottom line: The Velocity Micro ... Velocity Micro Vector Campus Edition

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In the recent 4th edition of Propellerhead Reason there is a handy floating Tools window that pops up on the right hand side by default. This tools menu contains the transpose, quantize, and velocity function shortcuts so you can reach them within one click. Using these functions in our song compositions allow us more creative possibilities.

1. Transpose. The transpose functions to raise or lower the key of the music we are making. Sometimes we want to try the song in a different key or raise the pitch of a particular part without having the re-record the performance. The transpose function allows us to control the pitch of the song globally or for a selected track.

2. Quantize. One of the most important advantages of making music with MIDI is the ability to quantize, or correct our performance errors, whether caused by computer gli tches or our own faulty performance. The quantize function corrects timing errors by shifting the recorded MIDI data to a quantize grid. Examples of quantize grids often used are 1/8th and 1/16th notes. Some musicians prefer to not use quantize when they need a human feel to the rhythm of the song, while other genres, such as dance and hip-hop, demand machine-like accuracy that may be difficult to achieve using conventional methods of playing.

3. Velocity. Velocity responds to the volume level of the MIDI data. By controlling the velocity value of the MIDI performance, we can make an instrument sound louder or softer, or just turn down a specific part of the track. When recording MIDI triggered drum samples in songs, drawing in the MIDI data causes the drum sounds to sound lifeless and dull. Using Reason's "Random" function in the velocity menu, we can introduce random fluctuations in the MIDI data in order to achieve a more humanistic feel to the rhyt hm part, if that's what we're after.

This has been a short article on the editing functions in Reason. I hope it helps you to better edit and tweak your performances.

To your musical perfection,Endy

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