1. NM Unit 6 Topic: Work and Energy Learning Goals: Identify the types of energy that make up the total energy of a system Predict changes in mechanical energy when positive or negative work is done on the center of mass Analyze a system and categorize the internal energy as potential, kinetic, or some combination of potential and kinetic. Solve problems involving work, power, and/or energy Solve problems involving the Work-Energy Theorem

2. Work and Energy Both scalar quantities Both have units of Joules Oh, and there is this weird equation thing...

3. Work changes energy? What kind of energy (or energies) do we have? Specifically how can work change that type of energy?

4. Work and Kinetic Energy A 9kg bag is being pushed from rest 5m across a smooth floor with a force of 11N. After being pushed 5m the bag has a velocity of 3.5 m/s (a) Calculate the work done on the bag (b) Calculate the change in kinetic energy

5. Work and Potential Energy A factory worker lowers a 15kg crate from a shelf 1.78 m above the ground to the ground. The crate is being lowered at a constant velocity. (a) What is the work done on the crate by the worker? (b) What is the change in gravitational potential energy of the crate?

6. Power and Energy/Work Revisit Power is the rate at which work is done or energy is converted. Watts are J/s The wattage of something is the “conversion rate”. A 60W lightbulb converts 60J/s of electrical energy into heat and light.