QUIZ 1. What is work in physics essentially the same thing as? a. Power b. Change in energy c. Displacement d. Force Answer: b. Work involves any of these things but is essentially the same thing as a change in energy, which does involve forces, movement, and displacement, but is not the same thing as these things. Power is related to work but is not the same thing. 2. How is work related to force? a. Work is equivalent to force over a period of time. b. Work is equivalent to force multiplied by a specific constant. c. Work is equivalent to force multiplied by the distance it acts on. d. Work is equivalent to potential energy multiplied by force. Answer: c. Work is proportional to force but it is only that component of force that is acted upon over a certain distance. 3. In the equation in which work is equal to the Force times distance times the cosine of theta, what does theta represent? a. The angle between the normal weight and the horizontal direction. b. The angle between the force vector and the displacement vector. c. The angle between a pulley system vector and the applied force on the system. d. The angle between the force vector and the y-axis. Answer: b. This is actually very simple. When doing work equations, you take the magnitude of the force vector times the magnitude of the direction/displacement vector and the cosine of the angle theta, which is the angle between them in degrees.
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