5. A box is pushed with a constant velocity across a desk with an applied force of 12 N [E]. The box has a mass of 40 kg. a. Draw a free body diagram of the box. (1 mark) b. What is the normal force acting on the box? (2 marks) What is the force of friction acting on the box? (2 marks) d. What is the coefficient of friction between the box and the desk? (2 marks) 6. Calculate the AMA of a lever with a load force of 90 N and an effort of 220 N. (3 marks) 7. Calculate the IMA of a lever with a load arm of 0.80 m and an effort arm of 1.2 m. (3 marks) 8. A bear pushes a camping cooler across a campsite with a force of 9 N. An opposing force of friction of 0.5 N acts on the cooler. The bear manages to push the cooler a distance of 10 m before being startled by an even bigger bear wanting the cooler. a. How much work is done by the applied force? (2 marks) b. How much work is done by friction? (2 marks) c) How much useful work is done? (2 marks) 9. An object hits the ground with a kinetic energy of 12 J. If its mass is 1.6 kg: What was its speed at impact? (3 marks) b. What height did the object fall from? (3 marks)