In eq. (10.1) in the lab manual, the constant rhoυ is 41.1 gm-cm^{-2} −2 sec^{-1} −1  in air. a piece of paper has a mass per unit area of approximately 7x10^{-3} −3 gm/cm^{2} 2 . if the frequency is 3.6 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.)

Electric field of the earth. the earth has a net electric charge that causes a field at points near its surface equal to 150 n> c and directed in toward the center of the earth. (a) what magnitude and sign of charge would a 60-kg human have to acquire to overcome his or her weight by the force exerted by the earth’s electric field? (b) what would be the force of repulsion between two people each with the charge calculated in part (a) and separated by a distance of 100 m? is use of the earth’s electric field a feasible means of flight? why or why not?