A crate of mass 12 kg is pulled a distance of 8 m up a rough slope inclined at an angle α \alpha\,α to the horizontal, where sinα=0.6\sin\alpha = 0.6sinα=0.6, as shown in the diagram below.
The crate is pulled at a constant speed by a force P P\,P parallel to the slope. The coefficient of friction between the crate and the slope is 0.3.
Taking g=9.8 m s−2g = 9.8\text{ m s}^{-2}g=9.8 m s−2, calculate the work done by the pulling force P P\,P to 3 significant figures.
226 J226\text{ J}226 J
564 J564\text{ J}564 J
734 J734\text{ J}734 J
790 J790\text{ J}790 J