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Today, we are transitioning into talking about energy and are going to start small and examine energy from a few different scenarios. These scenarios highlight the idea of choosing systems and will ask you to analyze each problem from two different systems. This will hopefully help you all compare and contrast these two different approaches to solving energy problems.
Project 7: Learning issues
- Relationship Between Force and Energy - Work
- Choosing a system
- Conservation of Energy
- Potential and Kinetic Energy
Scenario 3: Hawkeye Launches Arrow
Hawkeye is standing the edge of a tall building (80 m) and needs to fire an arrow into the sky as a warning to the other avengers. He releases the arrow with an initial speed of 50 m/s at an angle of 60 degrees. Consider this situation from the instant after the arrow is launched.
Choice 1: System = Arrow + Earth Choice 2: System = Arrow
1. For each choice of system above, answer the following questions:
- Is energy conserved in the system? Why/why not?
- Is work done on the system? Is it positive or negative? How do you know?
- Draw the energy bar charts for the scenario.
2. Pick a system to calculate the maximum height that the arrow will reach in the sky.
3. Which system did you choose for your analysis? Why?