Question

The following is not the method of reducing friction:

• A. using ball bearings
• B. applying grease
• C. applying paint
• D. forming a thin air cushion

Hint:

When dealing with friction-related questions, consider the type of contact (sliding vs. rolling) and whether lubrication or smooth surfaces are involved.

Answer 1

The Correct Option is C

Friction is the resistance to motion between two surfaces in contact. Methods of reducing friction typically involve reducing the surface roughness, introducing lubrication, or using rolling motion instead of sliding. - Using ball bearings reduces friction by converting sliding motion to rolling motion, which is a very effective way to reduce friction. - Applying grease is a method of reducing friction by lubricating the contact surfaces, which reduces the friction between them. - Applying paint does not necessarily reduce friction in most cases. In fact, depending on the type of paint, it might increase the friction or have no effect at all. - Forming a thin air cushion is another effective method of reducing friction, commonly seen in systems like air hockey tables, where a thin layer of air reduces contact between surfaces. Thus, the correct answer is option (3), applying paint, as it is not a method for reducing friction.

Answer 2

Step 1: Understand friction reduction methods
Common methods to reduce friction include lubrication, using ball bearings, polishing surfaces, and using smooth materials.

Step 2: Analyze the given option
Applying paint generally creates a coating on the surface which may increase roughness or adhesion, potentially increasing friction rather than reducing it.

Step 3: Conclusion
Therefore, applying paint is not a method used to reduce friction.

Final answer: Applying paint is not a method of reducing friction.