In anime teasing master takagi-san, Takagi says な~んだ そんなもんか after Nishikata claims he can skip a rock 15 times. From what i found online it sound like shes saying i dont believe that claim.
そんな such, that kind of.
もんか As if, there’s no way ~.
But the next sentence is clear nishikata thinks shes implying she can skip more. 15回より上をいくというのか
Can someone explain how そんなもんか is being translated? Thanks,
もの/もん is basically "thing", but it has a wide variety of usages, including these, and it can often refer to abstract things or ideas. Although もんか can sometimes mean "there's no way", this sense is irrelevant in your sentence.
Here, そんなもん is more like "(just) that much" rather than "such a kind of thing". なんだ said before it is an interjection that indicates the speaker's disappointment. か is a question marker.
なんだ、そんなもんか。
Oh, is that it? / Really, is that all? / Huh, just that much?
Another important meaning of そんなもん as a set phrase is "how it is" or "how it works":
「努力しているのにうまくいかない。」
「人生はそんなもんですよ。」"No matter how hard I try, things don't go as planned."
"That's just how life is."
