College Physics with MasteringPhysics 7th Edition by Jerry Wilson,Anthony Buffa,Bo Lou

تمرين 26

A father pushes horizontally on his daughter's sled to move it up a snowy incline, as illustrated in Fig. b. If the sled moves up the hill with a constant velocity, how much work is done by the father in moving it from the bottom to the top of the hill (Some necessary data are given in Exercise.)

FIGURE Fun and work See Exercise.
Exercise
A father pulls his young daughter on a sled with a constant velocity on a level surface a distance of 10 m, as illustrated in Fig. a. If the total mass of the sled and the girl is 35 kg and the coefficient of kinetic friction between the sled runners and the snow is 0.20, how much work does the father do

FIGURE Fun and work See Exercise.