The entire class goes for a hike. We all pick up rocks from the valley and carry them up to Frenchman Mountain, east of Las Vegas, where we stack them up on the peak. Subsequently, the pile collapses and all the rocks roll back down the mountain to the valley
below where we originally collected them. Answer the following questions:
1. What energy changed by moving the position of the rocks from the valley to the peak. Explain your answer.
2. What type of energy did the work to move the rocks to the peak? Where did that energy originally come from?
3. What type of energy was used as the rocks rolled back down the mountain?
4. If the rocks were moved from point A (the valley) to point B (the peak) and subsequently rolled back down to point A was the
overall energy used zero since they ended up back where they started? Explain why or why not.