Question

Which of the following happens when a lubricant is applied between two surfaces?

• A. The lubricant reacts with the surface impurities.
• B. The lubricant heats up the surfaces
• C. The lubricant increases the amount of interlocking between the surfaces.
• D. The lubricant decreases the amount of interlocking between the surfaces.

Answer 1

The correct option is D

The lubricant decreases the amount of interlocking between the surfaces.

The friction is caused due to the interlocking of irregularities between two surfaces. When the lubricant is applied, it forms a layer between the two surfaces. Hence, the irregularities are prevented from interlocking and friction decreases between two surfaces.