Answer:
In 2/4 time signature, an 8th rest equals half a beat.
Step-by-step explanation:
To make sense of this answer, you need to understand how time signature affects the score. We'll use 2/4 as an example for this.
Let's start by looking at the "Rhythm Tree", with the Whole note at the beginning; each note divides into 2 notes, both of which are half the value of the original note. (See attached image noº 1, keep this in mind for later)
Then, we need to know the meaning behind the two numbers of the time signature (see attached image noº 2).
- The top number indicates the amount of beats per measure.
- The bottom number (usually a power of 2) indicates which note constitutes one beat.*
* This is where the Rhythm Tree becomes relevant.
Basically, the bottom number is telling us how many times was the Whole note divided (or "branched off").
As for the 2/4 time signature:
- The top number is 2, so... 2 beats per measure.
- The bottom number is 4... And what do we get if we divide the Whole note 4 times? That's right: Quarter notes, this is the note that gets the beat.
This leaves us with the following values: A half note equals 2 beats, a quarter note equals 1 beat, an eighth note equals a half (1/2) beat, a sixteenth note equals a quarter (1/4) beat, and so on... (Same with rests)
Therefore, in a 2/4 time signature, a measure equals two quarter notes, or any combination of notes that has the equivalent value of two quarter notes:
- 2 quarter notes
- 1 eighth rest and 3 eighth notes
- 1 half note
- 8 sixteenth notes
- 1 quarter rest and 2 eighth notes
- 1 dotted quarter note and 2 sixteenth notes
- 2 eighth notes and 1 quarter note
You can see these examples in the attached image noº 3, which I sketched quickly in Sibelius (a score writing software) for visual reference.
There are many more possible combinations you can write besides these examples, just make sure that they amount to the same value as two quarter notes per measure.
Hope this helped clear your doubts, if there's anything you don't understand, feel free to ask.