"Panic" is considered an open syllable because it ends with a vowel sound, specifically the short "i" sound. In linguistic terms, an open syllable is one that ends in a vowel sound, while a closed syllable ends in a consonant sound. In this case, the "i" in "panic" creates an open syllable.
Photo is an open syllable word.
It is an open syllable.
First syllable closed, second syllable open.
Closed
Closed
The second syllable is open, the first is closed.
Paper is a closed syllable word.
Both open syllables.
Both closed.
It's a closed syllable.
It's a closed syllable.