Click the pictures and listen
This is a short vowel.
The mouth is held half open in a fixed position. The tongue is held flat and the tip is touching where the bottom teeth meet the gum inside the mouth. Resonance is at the back of the mouth.
There are lots of words where the letter 'o' is sounded as ʌ
pronunciation, up, cup, drum, butter, but, fun, us, mud, hunt, funny, cup, lunch, run
other, cover, love, money, done, son, above, other, brother
Courage, rough (/f/), country, tough, young, flourish