Different dictionaries use different symbols to transcribe the same sound. So you'll see different transcriptions such as:
The last syllable is unstressed and has an obstruent (/t p k s z/ etc) followed by a sonorant (/l m n/ etc). When an obstruent is followed by a Sonorant in the same unstressed syllable, the sonorant is usually syllabic (i.e. it forms a syllable on its own).
The same thing happens in the last syllable of physical. The /l/ is syllabic and the air is released laterally, so some dictionaries transcribe it /ˈfɪzɪkl/ or /ˈfɪzɪkl̩/. Most people, however, pronounce it with an intervening vowel, so some dictionaries transcribe it with a vowel: /ˈfɪzɪkəl/.
Other examples are:
- bottle → /ˈbɒtəl/ or /ˈbɒtl̩//
- button → /ˈbʌtn̩/ or /ˈbʌtən/
- prism →/ˈprɪzəm/ or /ˈprɪzm̩/
- -ism → /-ɪzəm/ or /-ɪzm̩/
(In the last three words, the air is released nasally.)
Both the transcriptions are correct. Also note that dictionaries are often inconsistent with their use of IPA.