Prove the design criteria and Grashof criteria for a double-rocker 4-bar mechanism. Design criterion for double-rocker: L2 = Lmin. Grashof criteria: Lmin + Lmax < La + Lb After you’ve proven that Lmin = L2 you should be able to identify or create (from your 6 triangle inequalities) three expressions that fit the Grashof criteria, one for each possible Lmax.

To save energy, the air supply to a 2000 ft office has been shut off overnight and the room temperature has dropped to 40°f. in the morning, the thermostat is reset to 70°f and warm air at 120 f begins to flov in at 200ft'/min. the air is well mixed within the room, and an equal mass flow of air at room temperature (changing with time) is withdrawn through a return duct. the air pressure is nearly 1 atm everywhere. ignoring heat transfer with the surroundings and kinetic and potential energy effects, estimate how long it takes for the room temperature to reach 70°f. plot the room temperature as a function of time.