Hi, I'm new to this forum. I'm currently doing a project on the coefficients of different materials used in sports so as to study the effects they have in their respective sports. Because we lack the equipment and knowledge to calculate drag, i'd like to ask whether a material having high friction on a ramp would equate to proportionately high friction in water/air? I base this on the fact that friction includes surface roughness, and since water and air can get into these small 'pockets' in the material, it would somehow create drag? Can anyone please verify this? And it would help a great load if there is any references as i need to answer to the skeptical judges.