Overtone

Natuurwetenskappe Gratis Graad 8 Vraestelle En Memorandums ❲Pro❳

Sukses in Natuurwetenskappe kom deur herhaling. Deur gebruik te maak van , verander jy abstrakte teorie in praktiese vaardighede. Begin vroegtydig met voorbereiding sodat jy met kalmte en selfvertroue die eksamenlokaal kan binnestap.

Hierdie webwerwe is goudmyne vir Suid-Afrikaanse kurrikulummateriaal. Hulle bied dikwels vraestelle aan wat spesifiek op die KABV (CAPS)-kurrikulum gebaseer is.

Om vertroud te raak met die struktuur van Afdeling A (Objektiewe vrae) en Afdeling B (Gevallestudies en berekeninge). natuurwetenskappe gratis graad 8 vraestelle en memorandums

NW-vraestelle bevat dikwels sketse van stroombane of selle. Oefen om hierdie diagramme akkuraat te benoem. Gevolgtrekking

In hierdie artikel kyk ons na waar jy die beste bronne kan vind, hoe om dit te gebruik, en watter afdelings van die kurrikulum die meeste aandag verg. Hoekom is ou vraestelle belangrik? Sukses in Natuurwetenskappe kom deur herhaling

Daar is verskeie betroubare platforms wat Afrikaanse hulpbronne gratis beskikbaar stel:

Baie topskole laai hul kwartaallikse toetse en eksamens op vir openbare gebruik. NW-vraestelle bevat dikwels sketse van stroombane of selle

Het jy hulp nodig met 'n spesifieke onderwerp soos of die periodieke tabel om jou vraestel-oefening aan te vul?

Examples

In synthesizer experiments you select the amplitudes and phases of the fundamental and 9 overtones to construct the beginning of a Fourier series. The sum is seen on a graphics display and the signal is available as sound card output.

natuurwetenskappe gratis graad 8 vraestelle en memorandums

natuurwetenskappe gratis graad 8 vraestelle en memorandums

natuurwetenskappe gratis graad 8 vraestelle en memorandums

You can test the Helmholtz assumption that the relative phases of the overtones are irrelevant to hearing.

In analyser experiments you capture sound from the sound card or from a WAV file up to several seconds long, select the starting time of the time slice and analyse time and frequency responses. The example shows the spectrum of a piano playing a middle C (262 Hz). The non-harmonic overtones are clearly seen. (Due to the stiffness of the string, the frequencies of the partials are too high.)

natuurwetenskappe gratis graad 8 vraestelle en memorandums

You may filter data with a digital filter and display spectrograms in color mode. This example shows the spectrogram taken from the word "harris" in the frequency range 0..10 kHz with a 4096-point-FFT every 2 ms (post processing). The formants of "i" and the high spectral components of "s" are clearly visible.

Sonogram

Short time spectral information may also be displayed in a 3-D representation, called "waterfall". The following example shows the waterfall spectrum of the same word "harris" as before. The red layer picks out the spectrum of "i" where the formants are visible again. The presentation may be rotated automatically or manually with scroll bars, in order to select the best "camera point".

natuurwetenskappe gratis graad 8 vraestelle en memorandums

Download version 1.15, June 2009: OVERTONE.ZIP (1.55 MB)

Unpack in a new folder, read README.TXT and start OVERTONE.EXE
(Some firewalls or User Access Control (UAC) may block execution. Give OVERTONE the necessary permissions.
Make sure, that the sound device is not used by another application.)

For more information, send e-mail to address given in README.TXT

Unterrichtseinheit Analyse von Klangspektren von Alain Hauser (in German)