1. A particular lever is 90.0% efficient. If 50.0 J of work are done on the lever, then how much work does the lever do on its load? 2.The mechanical advantage of a pulley system is 4.00. Using this pulley system, how much force do you need to exert to lift a 500.0 N box?

In eq. (10.1) in the lab manual, the constant is 41.1 gm-cmsec in air. a piece of paper has a mass per unit area of approximately . if the frequency is 4.8 khz, what does theory predict for the ratio of the transmitted amplitude to the incident amplitude of the sound wave? (a sound wave is a pressure wave.)