An experiment is being designed to measure aerodynamic forces on a building. the model is a 1/550 scale replica of the prototype. the wind velocity on the prototype is 58 ft/s, and the density is 0.0024 slugs/ft^3. the maximum velocity in the wind tunnel is 300 ft/s. the viscosity of the air flowing for the model and the prototype is the same. (a) find the density needed in the wind tunnel for dynamic similarity. (b) a force of 50 lbf is measured on the model. what will the force be on the prototype?

Afoot bridge is made as a simple deck, 4 m long, with a cross section 2 m (wide) and 20 cm thick, and made of wood. the deck is supported at the two ends. the maximum load allowable on the bridge is 10 tons, provided it is uniformly distributed on the deck. to sense this load, a strain gauge is placed at the center of the bridge and its resistance is monitored. if the sensor has a nominal resistance of 350 s2 and a gauge factor of 3.6, what is the reading of the strain gauge at maximum load? the modulus of elasticity for the wood used in the construction is 10 gpa.