路面阻力 meaning in English

surface resistance

The road with least resistance . .
路面阻力最小… …
The calculating formulas show that braking distance depends on initial braking speed , road dragging coefficient , mad slope grade , braking force increasing time ; and nothing to do with total mass of crane
计算公式表明：决定汽车起重机制动距离的主要因素是制动初速度、路面阻力系数、道路坡度和制动力增加时间；汽车起重机总质量与制动距离无直接关系。