The shape of a quarter note is as follows:

1. In music notation, a quarter note is usually represented as a normal note without any tail or additional dot. Its shape is a circle with a filled dot in the middle. This dot represents the head of the note, while the tail of the note is omitted. When playing and singing music, the length of a quarter note is often related to the rhythm of breathing and articulation, as well as the speed of the music.

2. When playing music, the quarter note is usually regarded as a basic rhythm unit. Its length can be evenly distributed among the four beats of the measure in sequence. For example, in a measure with 60 beats per minute, the length of each quarter note is 1/4x60=15 seconds.

3. When singing or playing an instrument, the length of the quarter note is usually related to the rhythm of breathing and pronunciation. In faster music tempos, a quarter note may be played faster, while in slower music tempos it may be played slower. A quarter note is one of the basic units of time in music, its length is equal to a quarter of a beat in a full measure.

The origin of the quarter note

1. The quarter note is one of the most basic notes in music, and its origin can be traced back to ancient times. In ancient Greece and Rome, music was divided into intervals, each with a specific name and symbol. Among them, the quarter note is used to represent a quarter of a complete interval, so it is called quaternarius.

2. In the Middle Ages, musicians began to use letters to represent the length and height of notes. This method was called Newm notation. During this period, a quarter note was represented as a letter without a tail, such as H or F, while a whole note was represented as a letter with a tail, such as B or S.

3. During the Renaissance, musicians began to use more complex symbols to represent the length and height of notes. Among them, the quarter note is represented as a small circular symbol with a filled dot in the middle. This symbol is called a crotchet. During the Baroque period, musicians began to use more elaborate symbols to represent the length and height of notes.