Does the word black have a short a or long a?

"Black' has a short 'a' sound, so it is pronounced 'blak'. Here is a little rule to remember: When there is only ONE vowel in a Word, and it is in the MIDDLE of the Word (that is, it is surrounded by consonant sounds), the vowel will FREQUENTLY be short.

For example, here are some Words that have short vowel sounds - 'cat, ham, pot, log, cub, fun, pet, men, lip, sit, fish, frog, flag, drip, chop, shop, pond, black, block, brick, trap, track, truck, stuck, trust, shrug, stand, stamp, strap, branch, flip, crumbs, thumb, thrill, club, brick, think, grad, spend, spell'.