On or near the last word
The nucleus is usually located on or near the last word of the intonation phrase. By definition, the nuclear accent is the last accent in the IP. So clearly the general tendency is for the nucleus to be towards the end of the IP. Provided that the last word in an IP is important for the meaning, it will be accented and thus bear the nucleus:
I ▸want to buy a 'lemon.
The ▸bridge is about to col'lapse.
She's ▸just started a new re'lationship
▸Could you tell me the 'time?
It is only if the words towards the end of the IP are for some reason not accented that the nucleus will go on an earlier word.
The ▸bridge is about to col'lapse.
She's ▸just started a new re'lationship
▸Could you tell me the 'time?
Initials, names of letters and numerals are treated like separate words. In a string of several letters or numerals, the nucleus generally goes on the last one:
In the e'xam | she got a 'C
My ▸room number is 50'6. (= five oh 'six)
▸Switch over to IT'V. (= eye tee 'vee)
My ▸room number is 50'6. (= five oh 'six)
▸Switch over to IT'V. (= eye tee 'vee)