page 07 MARKS 16. A box of mass 3 kg sits on a rough slope inclined at an angle of 50° to the horizontal. The box is attached to a light inextensible string which passes up the slope and over a smooth fixed pulley to a free hanging mass of 3.4 kg. pulley The box is on the point of moving up the slope. (a) Calculate the coefficient of friction between the box and the slope. The 3.4 kg mass is removed, and the box slides down the slope. (b) Calculate the time it will take for the box to travel 8 metres down the slope, given that it does not reach the bottom of the slope during this time. 17. (a) Use integration by parts to find sin 2 x x dx  . A solid is formed by rotating the curve with equation sin 2 y x x  between 0 x  and 1 x  through 2π radians about the x‑axis. (b) Calculate the volume of this solid. [Turn over 3 3 3 3