Something which is "insurmountable" is something which can not be overcome - as in:- Insurmountable technical problems brought an end to the project.
impossible
"Insurmountable" means that something can't be overcome, as in an "insurmountable obstacle".
It is better to use "insurmountable." "Insurmountable" is the correct spelling and means something that cannot be overcome.
Incapable of being passed over or overcome.
They are insurmountable and unsurmountable
An obstacle may seem insurmountable.
The mountain we tried to climb was insurmountable.
impossible
Despite insurmountable obstacles in his life, he had done very well.
Inertia indicates to scientists resistance to change in velocity.
It means it is incapable of being surmounted, passed over, or overcome. (It's powerful)