The sounds are different. The difference is quite small but also clear to a native speaker. It's important to learn how to hear the difference between the sounds. For US English pronunciation, there is a great website called "Rachel's English", which has video explanations.

I've never seen this symbol /∧/ in phonetics before, sorry. But /ɑ/ is pronounced like arm or art, with a long, deep "aah" You can check the phonetics and recorded sound of any word on this dictionary if you just click the sound icon next to the word you search [emoji] http://www.dictionary.com/browse/arm?s=t