Identification Label the following examples of electricity as either “N” for naturally
occurring electricity, or "H" for human-harnessed electricity.
1. Lightning
2. Getting shocked as you walk across carpet and touch a
doorknob
3. Crank flashlight
4. Charging a cell phone
5. Clothes sticking to each other in the dryer
6. Turning on a television
7. Hair standing straight up after removing a wool hat

Awater slide of length l has a vertical drop of h. abby's mass is m. an average friction force of magnitude f opposes her motion. she starts down the slide at initial speed vi. use work-energy ideas to develop an expression for her speed at the bottom of the slide. then evaluate your result using unit analysis and limiting case analysis. express your answer in terms of the variables h, m, l, vi, f and appropriate constants. vf v f