Find the net work done on the box as it moves from x = 0 m to x = 8.0 m. . Submit Request Answer Part B Apply concepts of work and energy to solve for the speed of the box when it reaches position x = 8.0 m. Assume the box started from rest.

Part A Suppose a box is being pulled horizontally a distance d with two forces acting on it, one along the direction of motion (F1) and the other at an angle 0 above the horizontal (F2). What is the net work done on the object by these forces? Express your answer in terms of some, all, or none of the variables F, F2, d, and 0. HVα ΑΣ φ W = Submit Request Answer

An object moving in the xy-plane is subjected to the force F = (2xyî+x²) N, where x and y are in m. Part A The particle moves from the origin to the point with coordinates (a, b) by moving first along the x-axis to (a,0), then parallel to the y-axis. How much work does the force do? Express your answer in terms of the variables a and b. W = Submit Part B W = Π| ΑΣΦ Submit Request Answer The particle moves from the origin to the point with coordinates (a, b) by moving first along the y-axis to (0, b), then parallel to the x-axis. How much work does the force do? Express your answer in terms of the variables a and b. V—| ΑΣΦ ? Request Answer ?

As shown in the figure below, a skateboarder starts at point A on the ramp and rises to point B, a maximum height of h = 2.83 m above the top of the ramp. If the amount of work done against friction is insignificant, determine his initial speed at point A. m/s A

A force of 570 N keeps a certain ideal spring stretched a distance of 0.900 m. Part A What is the potential energy of the spring when it is stretched 0.900 m? Express your answer with the appropriate units.

Review Istants Sam, whose mass is 72 kg , straps on his skis and starts down a 64 m -high, 20° frictionless slope. A strong headwind exerts a horizontal force of 200 N on him as he skies. Part A Use work and energy to find Sam's speed at the bottom. Express your answer to two significant figures and include the appropriate units. µA ? Value Units V = Submit Request Answer

Three different objects, all with different masses, are initially at rest at the bottom of a set of steps. Each step is of uniform height d. The mass of each object is a multiple of the base mass m: object 1 has mass 4.90m, object 2 has mass 1.46m, and object 3 has mass m. When the objects are at the bottom of the steps, define the total gravitational potential energy of the three-object system to be zero. If the objects are then relocated as shown, what is the new total potential energy of the system? Each answer requires the numerical coefficient to an algebraic 2 expression. Each algebraic expression is given using some 3 combination of the variables m, g, and d, where g is the acceleration due to gravity. Enter only the numerical coefficient. (Example: If the answer is 1.23mgd, just enter 1.23) U g,system mgd

A 1.77 kg book slides 1.25 m along a level surface. The coefficient of kinetic friction between book and surface is 0.145 Part A Find the work done by friction Express your answer with the appropriate units. ? HA Value Units W = Request Answer Submit

Review I A system in which only one particle can move has the potential energy shown in (Figure 1) . Suppose U1 = 88 J. Part A What is the y-component of the force on the particle at y = 0.5 m ? Express your answer to two significant figures and include the appropriate units. µA ? Fy = Value Units Submit Request Answer Part B Figure 1 of 1 What is the y-component of the force on the particle at y = 4 m? Express your answer to two significant figures and include the appropriate units. U (J) U HÀ ? Fy Value Units Submit Request Answer У (m) 5 0 - 1 3 4 Provide Feedback

A 1400-kg elevator is lifted at a constant speed of 1.5 m/s through a height of 25 m. Part A How much work is done by the tension in the elevator cable? Express your answer to two significant figures and include appropriate units. ? Value Units Submit Request Answer Part B How much work is done by gravity? Express your answer to two significant figures and include appropriate units. HẢ ? Value Units