Consider a smooth sphere, of diameter d, immersed in a fluid moving with speed v. the drag force on a 15-ft diameter weather balloon in air moving at 6 ft/s is to be calculated from test data. the test is to be performed in water using a 3-in. diameter model. under dynamically similar conditions, the model drag force is measured as 0.94 lbf. evaluate (a) the model test speed. (b) the drag force expected on the full-scale balloon.

If you were designing a bumper for a car, would you prefer it to exhibit elastic or plastic deformation? why? consider the functions of a bumper in both a minor "fender-bender" and a major collision.

Adouble-strand no. 60 roller chain is used to transmit power between a 13-tooth driving sprocket rotating at 300 rev/min and a 52-tooth driven sprocket. a) what is the allowable horsepower of this drive? b) estimate the center-to-center distance if the chain length is 82 pitches. c) estimate the torque and bending force on the driving shaft by the chain if the actual horsepower transmitted is 30 percent less than the corrected (allowable) power.

Thermal stresses are developed in a metal when its a) initial temperature is changed b) final temperature is changed c) density is changed d) thermal deformation is prevented e) expansion is prevented f) contraction is prevented