Is rug a short U vowel sound?

Answer 1

YES.

and this is how you can tell: if the U makes the same sound as the way you would say the letter in the alphabet, then it is long. if the U sounds different from the way you say it in the alphabet it is short.

Answer 2

Yes, "rug" contains a short U vowel sound (/ʌ/), as in words like "cup" or "luck." The short U sound is typically referred to as the "ah" sound in American English pronunciation.

Answer 3

Yes it is a short sound