It measures the force of a blow (4,5)

'it measures the force of a blow' is the definition.
The definition suggests a singular noun which matches the answer.

'it measures the force of a blow' is the wordplay.
I cannot really understand how this works, but
'it' could be 'e' ('e' can mean 'electronic' which is similar to 'IT') and 'e' is found within the answer.
'force' could be 'g' (short for gravity) and 'g' is found within the answer.
'a' is found in the answer.
'blow' could be 'wind' and 'wind' is located in the answer.
The remaining letters 'ug' 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?