Which statement represents how light travels? Light given off from a moving source will travel faster in a vacuum. Light given off from a moving source will travel faster in air. Light travels slower if the light source is moving. Light travels at the same speed even if the light source is moving.

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