developed in the tutorials. 3. Imagine now that the people exert forces in the same directions as before, but the sled now S IN EDUCATIONAL INNOVATION moves with a constant velocity to the left. (Remember, continue to neglect friction on the sled.) a. Draw a free-body diagram for this case. Outside the box, draw the acceleration vector for assignments, Pretests are included in the vised tutorials on mechanics, electricity and the object, labeled with a . uctional materials to be most effective, it is roductory Physics builds upon the Preliminary rigorously class-tested at the University of namics, and modern physics, In all cases, a dents help one another go through the steps in include qualitative questions that emphasize in Introductory Physics is intended to supplement material students need more assistance than they iversities, and at two-year and four-year colleges ctures, reading the textbook, and solving standard which the Physics Education Group has sought to truction and application of important concepts and fficulties that students encounter in studying physics ts of a pretest, worksheet, homework assignment, rve as post-tests. The student texts consist of the is based on extensive teaching experience and more n the process of learning physics. The materials are motivated by the conviction that in order to develop b. Which person exerts a larger horizontal force? Explain. tion by providing a structure that promotes the active ased and calculus-based courses. Working together the First Edition also includes tutorials on selected 4. Imagine now that the two people exert forces in the directions as before, but the sled now accelerates to the left. a. Draw a free-body diagram for this case. Above, draw the acceleration vector for the object, labeled with a . b . Which force on the sled is larger in this case ? Explain . Tutorial Section 2.2 - Applying Newton's Second Law C. Choose a coordinate system with the positive x-direction to the left. Fill in the following The same two people from the last section exert forces on the sled, but now the sled has different equation based on your free-body diagram. outcomes. Neglect friction on the sled for the entirety of this section. EFF = mblockar = bris a'not 1. Complete the equation for the net force in the x-direction (Fretx or EF ) for the situation in Case 1 (from the previous section). To do this, use your free-body diagram from the last section. Choose Now consider the role of the coordinate system. Choose a coordinate system with the a coordinate system with the positive x-direction to the left. positive x-direction to the right. Fill in the following equation based on your free-body a. Use the convention that all variables are assumed to be positive (e.g. FPam's rope is a diagram. Compare it with your answer to part (c). positive number). This means + Pam's rope points in the positive direction and EFT = Mblockar = - FPam's rope points in the negative direction. Fnet,x = EFx = mblockaz = Imagine that the two people both exert stronger forces than before, but the sled still does not move. Redraw the free-body diagram in this case. Which forces have the same magnitude as above and which forces have different magnitudes? Explain your reasoning. asison pange esnon
