1- A horizontal force of 150 N is used to push a 40 kg box 6 m on rough horizontal surface. If the box moves at a constant speed, find a. The work done by the applied force b. The energy lost due to the friction. c. The coefficient of kinetic friction. 2- A force F = (6î - 2?) N acts on a particle that undergoes a Displacement ?r = (3î + ?) m Find a. The work done by the force on the particle b. The angle between F and r. 3- A 15.0-kg block is dragged over a rough, horizontal surface by a 70.0-N force acting at 20.0° above the horizontal. The block is displaced 5.00 m, and the coefficient of kinetic friction is 0.300. Find the work done on the block by a. The 70-N force. b. The normal force. c. The gravitational force. d. The energy lost due to the friction 4- The force acting on a particle varies as in Figure. Find the work done by the force on the particle as it moves a. From x = 0 to x = 8.00 m. b. From x = 8.00 m to x = 12.0 m. c. From x = 0 to x = 12.0 m. 5- A 0.600-kg particle has a speed of 2.0 m/s at point A and kinetic energy of 7.50 J at point B. What is a. its kinetic energy at A? b. its speed at B? c. the total work done on the particle as it moves from A to B?
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Given: Force (F) = 150 N Displacement (d) = 6 m Work done = F * d Work done = 150 N * 6 m Work done = 900 J Show more…
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