It depends on which instrument you're talking about.
For example, a Bass Guitar has 4 strings while a regular guitar has 6. Violins all have 4 strings, whether they are bass or not. Each musical instrument will have its own number of strings depending on what sort of instrument it is.
The usual number varies with the instrument. Violins and ukuleles have four.
Guitars usually have six, but some have as many as 11. Mandolins usually have 8 strings but some have 12 or 16. Banjos have 4 or 5.
It depends on which instrument you're talking about.
For example, a Bass Guitar has 4 strings while a regular guitar has 6. Violins all have 4 strings, whether they are bass or not. Each musical instrument will have its own number of strings depending on what sort of instrument it is.
Usually 4. (Viola, Violin, Cello, Bass).
Depends on the instrument.
Orchestral string instruments all use 4 strings.
A Bajo de uñas is an instrument that can have between 4 and 6 strings and is comparable to the double bass. The four stringed version of the instrument is much more common than the 6 stringed variety.
Atonality
Only the string holding the price tag. The sax is not a stringed instrument.
Usually 4. (Viola, Violin, Cello, Bass).
Harp
This varies from instrument to instrument - eg Guitar 6, Violin 4, Zither 34, Bandurria 12.
The shorter you make a string, the higher the pitch will be. You can notice that as someone plays the guitar, and they slide their fingers toward the body, the pitch gets higher. If you loosen a peg on a stringed instrument to elongate the string, the pitch drops because the frequency (how many vibrations per second) decreases.
4
Depends on the instrument.
I think you're getting slightly confused with your terminology. The 'string family' comprises all the bowed stringed instruments in a standard orchestra: violins, violas, cellos (violoncellos), and double basses. Thus there are four types of instrument in the string family.
Orchestral string instruments all use 4 strings.
The double bass has 4 strings. It is a classical instrument that is related to the violin and cello, but is the largest in this family.There are basses that have more strings, but they are usually electric instruments, such as 5 or 6 stringed basses. As well, there are 8 and 12 string basses that have "duplicate strings" that are tuned to a higher octave to it's root string (similar to a 12-string guitar).
Many different stringed instruments are used. Classical music is mostly played by violins, violas, cellos, and the double bass. Harps and pianos are also used.
Pianos, and harpsichords are both stringed instruments. When a key is pressed on a piano, a hammer hits one of they many strings hidden in the body. In contrast, harpsichords are plucked when keys are pressed.