The correct spelling of the word is "Sulfuric". The phonetic transcription in IPA is /ˈsʌlfjʊrɪk/ which indicates the pronunciation of the word. The letter "ph" in "sulphauric" is a common misspelling, as the chemical element with symbol S is spelled as "sulfur". The correct spelling in scientific and industrial usage is important as it can affect the accuracy of experiments and processes. Therefore, it is essential to learn and use the correct spelling of technical words in various fields of study.