Physicist's hesitation with car following reality (bonnet's missing) (10)
I believe the answer is:
rutherford
'physicist's' is the definition.
(Ernest Rutherford 1871-1937 nuclear physicist)
'hesitation with car following reality bonnet's missing' is the wordplay.
I cannot really understand how this works, but
'hesitation' could be 'er' (sound used when hesitating) and 'er' is found within the answer.
'car' could be 'ford' (Ford is a make of car) and 'ford' is present in the answer.
The remaining letters 'ruth' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for rutherford that I've seen before include "Scientist" , "Den" , "Actress" .)