AQA M1 2014 June — Question 3

Exam BoardAQA
ModuleM1 (Mechanics 1)
Year2014
SessionJune
TopicNewton's laws and connected particles

3 A skip, of mass 800 kg , is at rest on a rough horizontal surface. The coefficient of friction between the skip and the ground is 0.4 . A rope is attached to the skip and then the rope is pulled by a van so that the rope is horizontal while it is taut, as shown in the diagram.
\includegraphics[max width=\textwidth, alt={}, center]{788534a5-abbb-4d6a-87b2-c54e859a128a-06_237_1118_497_463} The mass of the van is 1700 kg . A constant horizontal forward driving force of magnitude \(P\) newtons acts on the van. The skip and the van accelerate at \(0.05 \mathrm {~ms} ^ { - 2 }\). Model both the van and the skip as particles connected by a light inextensible rope. Assume that there is no air resistance acting on the skip or on the van.
  1. Find the speed of the van and the skip when they have moved 6 metres.
  2. Draw a diagram to show the forces acting on the skip while it is accelerating.
  3. Draw a diagram to show the forces acting on the van while it is accelerating. State one advantage of modelling the van as a particle when considering the vertical forces.
  4. Find the magnitude of the friction force acting on the skip.
  5. Find the tension in the rope.
  6. \(\quad\) Find \(P\).
    \includegraphics[max width=\textwidth, alt={}]{788534a5-abbb-4d6a-87b2-c54e859a128a-06_771_1703_1932_155}