Why is 'Is your mother at her job' not correct? In similar situations this free translation was supported.
Why is it 'jobbet' doesn't jobbet mean the job?? So wouldn't it translate to 'is your mother at the work/job' which makes completely no sense
It's not always possible to translate word-for-word and get the same meaning. Swedish and English differ idiomatically here - one uses the definite to express something for which the other uses the indefinite.
The most direct translation from the Swedish would be "Is your mother at work?" Arbetar din mamma? would be a better way to say "Is your mother working?"
What is the exact translation of på? Because it can be use for on, during And wearing something??
There is no one exact translation - usually, it's "on", but it varies a lot.
Please refer to the top question of the FAQ: https://forum.duolingo.com/comment/20444477/FAQ-for-the-Swedish-course
"mom" is perfectly fine but I see you've reported "Is you Mom at work" - it should be "your" in English, not "you".
"at work" is a better translation in English. "the work" sounds very clumsy.