Which type of electricity is a one-time event, caused by unbalanced charges trying to become neutral again?

What are similarities and differences of reflection, refraction, diffraction and absorption?

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

Afrequency generator sends a 550 hz sound wave through both water and ice. what is the difference in wavelength between the wave produced in ice and the wave produced in water?