Activity No. 6WORK AND POWERI. Theory:The concepts of work provide a convenient means of analyzing an object or system ofobjects moving between an initial and final state. Basically, work is defined as the product offorce and distance. To express that mathematically these arew = F x d orw = m x g x hWhen work is done upon an object by an external force, the total mechanical energy (KE+ PE) of that object is changed. If the work is "positive work", then the object will gainenergy. If the work is "negative work", then the object will lose energy. The gain or loss inenergy can be in the form of potential energy, kinetic energy, or both. Under suchcircumstances, the work which is done will be equal to the change in mechanical energy ofthe object.In this experiment, we will utilize the concept of work by applying it to a studentperforming this experiment. A diagram below illustrates how the work is being utilized.dupFigure 12.1 Diagram of ladder a. Determine the work a hiker must do on a 15 kg backpack to carry it up a hill of height h =14 m;b. Determine the work done by gravity on the backpack; andc. What is the net work done on the backpack.Assume the motion is smooth and at constant velocity.

Mass of the backpack m=15 kg, height of the hill h=14 m and acceleration due to gravity. Let us take…

a. Determine the work a hiker must do on a 15 kg backpack to carry it up a hill of height h = 14 m; b. Determine the work done by gravity on the backpack; and c. What is the net work done on the backpack. Assume the motion is smooth and at constant velocity.

a. Determine the work a hiker must do on a 15 kg backpack to carry it up a hill of height h = 14 m; b. Determine the work done by gravity on the backpack; and c. What is the net work done on the backpack. Assume the motion is smooth and at constant velocity.

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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1. A spring (k=100 N/m) is hanging from the ceiling when somebody attaches a 2 kg block to the end of it and releases it. a. Identify all of the forces on the block after it is released. b. Which forces are in the direction of motion and which are in the opposite direction of motion? Which forces are doing positive work and which are doing negative work? c. Write an integral for the work done by gravity as the block falls from s=0 to s=x₁. Solve the integral with the start and end points at s=0 and s=xf. d. Write an integral for the work done by the spring as the block falls from s=0 to s=xf. Keep the signs correct. Solve the integral with the start and end points at s=0 and s=x₁. e. Use the work-kinetic energy theorem AK-Wnet to determine how low the block falls before turning around. (Note: the block has no velocity at its lowest point). f. When the block was first falling, what was its velocity when the spring stretched 20 cm?
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