Question

Friction is reduced by:
1. Making the surface moist
2. Making the surface rough
3. Sprinkling sand on the surface
4. Making the surfaces a little more smoother

• A. 2 and 3
• B. only 1
• C. 1 and 2
• D. 1 and 4

Answer 1

The correct option is D 1 and 4

Making the surfaces moist and smooth helps to reduce the friction between two bodies.
This is because any liquid acts as a lubricant and fills the fine pores or depressions on the surface, reducing the friction. This is why vehicles slip on moist roads.