Back to 'Unit 7: Work and Energy'

Topic outline

  • 7.2: Work, Potential Energy, and Linear Kinetic Energy

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    We define kinetic energy as the energy associated with motion. We calculate kinetic energy as {KE} = \frac{1}{2}mv^2 .

    When work is done on a system, energy is transferred to the system. We define net work as the total of all work done on a system by all external forces. We can think of the sum of all the external forces acting on a system as a net force, or F_{\mathrm{net}} .

    We can write the equation for net work in a similar way to how we wrote the equation for work earlier: W_{\mathrm{net}} = F_{\mathrm{net}}d\cos\theta , where W_{\mathrm{net}} is net work, F_{\mathrm{net}} is net force, d is displacement, and \theta is the angle between force and displacement.