meaning of シュワーっと


I'm currently reading a children's book about numbers with sentences of the
form:

[code]

    numberは　j1 j2
    
[/code]

where `j1` and `j2` are japanese words and `j1` starts sounding similar to
`number`.

I am stuck with

> 4は [シュワー]{しゅわー}っと しんかんせん

where the "ー" is 4 times the expected size and yes, after it comes hiragana. I
figure it means "4 stands for x shinkansens" as the page shows a picture of 4
smiling electric trains that are sorted by size.

However, I can not find a translation for シュワーっと, exept for `シュワシュワ ~
bubliness`. But I don't see sense in that. Could it be an onomatopoeia =
describing a sound? Also, why use 2 alphabets?




シュワー is the sound of something moving fast, in this case, a bullet train.

Onomatopoeia in Japanese is quite interesting. It plays a bigger role in
everyday Japanese than it does in everyday English. There is common
onomatopoeia for Japanese words where we have none for the same words in
English. And Japanese speakers will use often different onomatopoeia to
describe the same sound.

I remember watching a game show in Japan where participants had to identify
the nuances in sound conveyed by various onomatopoeia. For example, they were
debating about how ザー is the sound of strong rainfall, but ガー is the sound of
even stronger rainfall.

In your sentence, シュワー , like most onomatopoeia, is written in katakana. The
rest of the sentence is written in hiragana, as is typical for a children's
book.

As another user mentioned, っと immediately following the onomatopoeia makes it
clear that シュワー is a quotation.




シュワー is the sound of something moving fast, in this case, a bullet train.

Onomatopoeia in Japanese is quite interesting. It plays a bigger role in
everyday Japanese than it does in everyday English. There is common
onomatopoeia for Japanese words where we have none for the same words in
English. And Japanese speakers will use often different onomatopoeia to
describe the same sound.

I remember watching a game show in Japan where participants had to identify
the nuances in sound conveyed by various onomatopoeia. For example, they were
debating about how ザー is the sound of strong rainfall, but ガー is the sound of
even stronger rainfall.

In your sentence, シュワー , like most onomatopoeia, is written in katakana. The
rest of the sentence is written in hiragana, as is typical for a children's
book.

As another user mentioned, っと immediately following the onomatopoeia makes it
clear that シュワー is a quotation.

