QuesonlofS ) A small boat is crossing a lake on a wind)r day. During some interval of time, the boat undergoes the given displacement AF. :1? = (3.25 m)? + (2.?3 ml? During the same interval of time, the wind exerts the given constant force F' on the boat. F' = (255 N)? (123 N)j What is the total work done on the boat by the wind over this period of time? What is the angle between the direction of the wind force and the direction of the boat's motion during this time interval? angle: Question 2 of 5 A book slides across a level, carpeted floor with an initial speed of 3.85 m/s and comes to rest after 3.25 m. Calculate the coefficient of kinetic friction # between the book and the carpet. Assume the only forces acting on the book are friction, weight, and the normal force. H =Question5of5 > A spring with a spring constant of k = 95 burn is snatched a distance of Ax = 0.35 In from its relaxed position. By how much does the springs potential energy U. change? A scene in a movie has a stuntman falling through a oor onto a bed in the room below. The plan is to have the actor fall on his back, but a researcher has been hired to investigate the safety of this stunt. When the researcher examines the mattress, she sees that it effectively has a spring constant of 65144 NW for the area likely to be impacted by the stuntman, but it cannot depress more than 13.] 1 cm without injuring him. To approach this problem. consider a simplied version of the situation. A mass falls through a height of 4.12 to before landing on a spring of force constant 65144 me. Calculate the maximum mass that can fall on the mattress without exceeding the maximum compression distance. ' Based on this crude measurement, is the stunt safe using maximum mass: kg the proposed mattress? 0 cannot determine 0 3'65 0 no Warning: The safety of movie stunts is now heavily researched and involves more sophisticated computations than used here. Do not attempt stunts on your own. An m = 20.0 g object is held against the free end of a spring d of constant k = 25.0 N/m that is compressed a distance x = 10.0 cm from its equilibrium length. Once released, the - - object slides d, = 1.15 m across the tabletop and eventually lands d2 = 0.74 m from the edge of the table on the floor, as shown in the figure. Calculate the coefficient of friction / between the table and the object. The sliding distance includes the compression of the spring, and the tabletop is h = 1.00 m above the floor level. N =A child slides down a snowcovered slope on a sled. At the top of the slope, her mother gives her a push to start her oil" with a speed of LII] n1.-'s. The frictional force acting on the sled is one-fth of the combined weight of the child and the sled. If she travels for a distance of 24.5 m and her speed at the bottom is 4.05 mts, calculate the angle 3 that the slope makes with the horizontal. Robert has just bought a new model rocket, and is trying to measure its flight characteristics. The rocket engine package claims that it will maintain a constant thrust of 1].? N until the engine is used up. Robert launches the rocket on a windless day, so that it travels straight up, and uses his laser range-nder to meaure that the height of the rocket when the engine cuts off is 12.4 111. He also measures the rockers peak height, which is 16.9 m. If the rocket has a mass of 0.613 kg, how much work is done by the drag force on the rocket during its ascent? A 8.10 x [Uskg car is travelling 180.? HUS when the driver decides to exit the freeway.r by going up a ramp. After coasting 3.90 x 102 m along the exit ramp, the car's speed is 11.8 INS, and it is h = 14.9 m above the freeway. What is the magnitude of the average drag farce Fug exerted on the ear'? Fdrag = N