In order to move a box filled with equipment to the second story loft in the warehouse, several students built a ramp or inclined plane. there was some disagreement on the height and material for the ramp. the loft height was 2.5 meters. sara suggested a very long ramp, approximately 25 meters long. the other students disagreed, insisting it would take too much effort to push the box that distance and the ramp should be much shorter and steeper. instead they built a ramp 10 meters in length. what comments would you make to the students based solely on the mechanical advantage of an inclined plane?

If a clock aboard a space ship traveling at 0.900 c of the speed of light relative to earth chimes once at the beginning of the hour and again when it reads one hour later, how much time would an observer on earth say elapsed between the two chimes?

Part f - example: finding two forces (part i) two dimensional dynamics often involves solving for two unknown quantities in two separate equations describing the total force. the block in (figure 1) has a mass m=10kg and is being pulled by a force f on a table with coefficient of static friction îľs=0.3. four forces act on it: the applied force f (directed î¸=30â above the horizontal). the force of gravity fg=mg (directly down, where g=9.8m/s2). the normal force n (directly up). the force of static friction fs (directly left, opposing any potential motion). if we want to find the size of the force necessary to just barely overcome static friction (in which case fs=îľsn), we use the condition that the sum of the forces in both directions must be 0. using some basic trigonometry, we can write this condition out for the forces in both the horizontal and vertical directions, respectively, as: fcosî¸â’îľsn=0 fsinî¸+nâ’mg=0 in order to find the magnitude of force f, we have to solve a system of two equations with both f and the normal force n unknown. use the methods we have learned to find an expression for f in terms of m, g, î¸, and îľs (no n).

Power can be defined as a. the distance over which work was done. b. how much work can be done in a given time. c. all the work in an given area. d. the energy required to do work.