TEST AS平均难道题目 。。自我检测~~

balance2323

In a steel mill, sheet steel is rolled onto cylinders at the end of the production process. When empty, the radius of one of these cylinders is r0 and the cylinder turns at a constant rotation speed n during the rolling process. The thickness of the sheet steel is expressed as d.

Which equation expresses the change in a cylinder抯 radius r in relation to the time t (in seconds)?

javascript:;

r=r0+nd/t   ?[attachimgjavascript:;]2752[/attachimg]