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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 4: Spiderman drops an apple
Spiderman is chilling on top of a skyscraper (120 m) eating his lunch, when he accidentally drops his apple. The apple then plummets toward an unsuspecting people on the street below.
Choice 1: System = Apple
Choice 2: System = Apple + Earth
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. Spiderman decides to shoot a web to try to catch the apple before it hits a person on the street. Pick a system to calculate how much work Spiderman must do to stop the apple before it hits someone.
3. Which system did you choose for your analysis? Why?