Answer pastpaper

Answer all the questions. Give non-exact numerical answers correct to 3 significant figures, or 1 decimal place in the case of angles in degrees, unless a different level of accuracy is specified in the question. Where a numerical value for the acceleration due to gravity is needed, use 10 m s-2. The use of an electronic calculator is expected, where appropriate. You are reminded of the need for clear presentation in your answers. At the end of the examination, fasten all your work securely together. The human action of marks is given in brackets at the end of each question or part question.The total number of marks for this paper is 50. Questions carrying smaller numbers of marks are printed earlier in the paper, and questions carrying larger numbers of marks later in the paper. This document consists of 3 printed pages and 1 blank page. UCLES 2011 Turn over 2 A car of clutch 700 kg is travelling along a straight horizontal road. The resistance to motion is constant and equal t o 600 N. (i) Find the whimsical force of the cars engine at an instant when the acceleration is 2 m s-2. Given that the cars speed at this instant is 15 m s-l , cars engine is working. recoup the rate at which theA load of mass 1250 kg is raised by a crane from rest on horizontal ground, to rest at a height of 1. 54 m above the ground. The work done against the resistance to motion is 5750 J. (i) Find the work done by the crane. (it) Assuming the power outturn of the crane is constant and equal to 1. 25 kW, find the time taken to raise the load. 3 q 15. 5 N A small smooth prognosticate R of weight 8. 5 N is threaded on a light inextensible string. The ends of the string are attached to fixed plosive consonants A and B, with A vertically above B. A horizontal force of magnitude 15. 5 N acts on R so that the ring is in equilibrium with ngle arbitrager = 900 .The part AR of the string makes an angle B with the horizontal and the part BR makes an angle B with the vertical (see diag ram). The tension in the string is T N. Show that T sin 12 and T cos B = 3. 5 and hence find B . 6 4 A discontinue of mass 11 kg is at rest on a rough plane inclined at 300 to the horizontal. A force acts on the block in a direction up the plane parallel to a line of greatest slope. When the magnitude of the force is 2X N the block is on the point of sliding down the plane, and when the magnitude of the force is 9X N the block is on the point of liding up the plane.