A worker pulls a wooden crate along a straight warehouse floor by exerting a constant force of 200N on a rope. The rope is kept taut and the crate moves 10m. The work done by the worker on the crate is measured to be −1000J.
(i) Calculate the angle between the force applied and the displacement of the crate.
(ii) Comment on the physical meaning of the negative sign of the work obtained in part (i).