Paper 4 October/November 2011 MATHEMATICS (9709/41) A Levels
لطفا برای اطمینان از عملکرد و تجربه بهتر از مرورگرهای مدرن و به روز مانند کروم یا فایرفاکس استفاده کنید.

A block is pulled for a distance of $50{\text{ }}m$ along a horizontal floor, by a rope that is inclined at an angle of ${\alpha ^ \circ }$ to the floor. The tension in the rope is $180{\text{ }}N$ and the work done by the tension is $8200{\text{ }}J$. Find the value of $\alpha $.