How can the percussion instruments be divided into two groups?
strings and nonstring instruments
If you're talking about meterology and the weather, the instrument that measures the wind is called an Anemometer. However, in terms of musical instruments, they are plainly refered to as the Wind Instruments, but can be further divided into two groups, the Brass Instruments and the Woodwind Instruments.
The four instruments that are in the Orchestra are Bass, Cello, Violin, and Viola. All four are in the Strings section. The other three sections are: Brass, Woodwinds and Percussion. Two instruments in each would be: Strings: Violin & Cello Brass: Trumpet & French Horn (also Trombone and Tuba) Woodwinds: Flute & Clarinet (also Oboe, English Horn and Bassoon) Percussion: Snare, Tympany (plus a variety of other percussion instruments.
The order of instruments in an orchestral score is traditionally arranged in four groups: woodwind, brass, percussion and strings, in that order, downwards. The woodwind instruments are arranged by the length of the instrument, beginning with the shortest (piccolo) at the top, followed by flutes, oboes, clarinets and bassoons. The brass section traditionally begins with the horns, followed by trumpets and trombones. The percussion usually includes two or more kettledrums (timpani), and perhaps a side-drum…
Do you mean Country and Western, or generally Western hemisphere music? The latter uses all sorts of drums, cymbals, wood blocks. There are many types of drums; snare drums, bass drums, congas, bongos, and kettle drums. Mallet instruments such as vibraphones, xylophones, and marimbas are also percussion instruments. Some styles of music use a washboard as a percussion instrument.
Answer Yes, it is. It uses a reed in the mouth piece, that makes it a woodwind. The woodwinds are divided into to major groups, one is flutes and whistles, and the others are instruments with reeds. The instruments with reeds are further divided between those with a single reed, which includes clarinets and saxophones, and those with two, which includes oboes and bassoons.
Which of these is not a category of percussion instruments chordophones membranophones or idiophones?
All can be considered as a percussion instrument but the Chordophone is not really a "Main" category in percussion. The two major category in percussion are Membranophones and Idiophones but there are chordophones that can be considered as a percussion instrument. An example of this is the piano. It produces sounds by its strings so its a chordophone but the strings are hit by little hammer so that they would vibrate and produce sound.
The instrumentation for Mozart's Idomeneo include woodwinds, brass, percussion, strings, and basso continuo. The woodwinds are piccolo, two flutes, two clarinets, two oboes, two bassoons, and B clarinets. The brass is four horns, two trumpets, and three trombones. The percussion is Timpani in A and D. The basso continuo includes harpsichord and violincello. There are also string instruments (violin, viola, cello, and double bass).
String instruments produce a softer sound than many of the others. To avoid drowning them out, the woodwinds and brass are farther from the audience. The percussion instruments are even further back. It is also the reason an orchestra will have two or three times as many string players as there are other instruments.