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The tray dispenser in your cafeteria has broken and is not repairable. The custodian knows that you are good at designing things and asks you to help him build a new dispenser out of spare parts he has on his workbench. The tray dispenser supports a stack of trays on a shelf that is supported by four springs, one at each corner of the shelf. Each tray is rectangular, with dimensions 45.3 cm by 35.6 cm. Each tray is 0.450 cm thick and has a mass of 580 g. The custodian asks you to design a new four-spring dispenser such that when a tray is removed, the dispenser pushes up the remaining stack so that the top tray is at the same position as the just-removed tray was. He has a wide variety of springs that he can use to build the dispenser. Which springs should he use?
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Chapter 7 Solutions
EBK PHYSICS FOR SCIENTISTS AND ENGINEER
- Embassy Motorcycles (EM) manufactures two lightweight motorcycles designed for easy handling and safety. The EZ-Rider model has a new engine and a low profile that make it easy to balance. The Lady-Sport model is slightly larger, uses a more traditional engine, and is specifically designed to appeal to women riders. Embassy produces the engines for both models at its Des Moines, Iowa, plant. Each EZ-Rider engine requires 6 hours of manufacturing time and each Lady-Sport engine requires 3 hours of manufacturing time. The Des Moines plant has 2100 hours of engine manufacturing time available for the next production period. Embassy’s motorcycle frame supplier can supply as many EZ-Rider frames as needed. However, the Lady-Sport frame is more complex and the supplier can only provide up to 280 Lady-Sport frames for the next production period. Final assembly and testing requires 2 hours for each EZ-Rider model and 2.5 hours for each Lady-Sport model. A maximum of 1000 hours of assembly and…arrow_forwardA tree contractor has been hired by a homeowner to remove a k damaged tree from a previous storm. The top of the tree broke off, leaving the trunk in the ground. The arborist will remove the tree by attaching a rope near the top and cutting the base close to the ground. The scenario is shown in the figure. 2 The distances in the figure are z = 14.7 m, h 1.45 m, h y = 5.66 m and x = 10.64 m. If the arborist pulls on the rope 1.. with a force of magnitude F 35.1 N, write the expression X for the torque T with respect to the base P of the tree using ijk unit vector notation, i i = T,i + Tyj + t;k where Tx, Ty» and Tz are the values of the torque components in the x-, y-, and z-directions, respectively. = N•marrow_forwardA person opens a door by applying a 13-N force perpendicular to it at a distance 0.90 m from the hinges. The door is pushed wide open (to 120 ° ) in 2.6 s How much work was done? Express your answer using two significant figures. να ΑΣφ J Submit Request Answer Part B What was the average power delivered? Express your answer using two significant figures. Hνα ΑΣφarrow_forward
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