A student group backed scientist (5)
I believe the answer is:
tesla
'scientist' is the definition.
(I've seen this before)
'a student group backed' is the wordplay.
'student' becomes 'l' (as in L-plates for learner drivers).
'group' becomes 'set' (both can mean a collection).
'backed' says the letters should be written in reverse.
'a'+'l'+'set'='alset'
'alset' backwards is 'TESLA'.
(Other definitions for tesla that I've seen before include "American scientist" , "Physicist" , "Nikola ---, electricity pioneer" , "electrical unit" , "Physics unit" .)