Question

question:
oil is used between two facing surfaces, such as pistons and cylinders, to overcome
____.

answer input:
spelling counts but capitalization doesnt.

Explanation:

Oil is used as a lubricant between two facing surfaces (like pistons and cylinders) to reduce friction. Friction is the force that opposes motion between two surfaces in contact, and using oil (a lubricant) helps overcome this resistance.

Answer:

friction