You’re engineering an energy-efficient house that will require an average of 6.85 kW to heat on cold winter days. You’ve designed a photovoltaic system for electric power, which will supply on average 2.32 kW. You propose to heat the house with an electri-cally operated groundwater-based heat pump. What should you specify as the minimum acceptable COP for the pump if the pho-tovoltaic system supplies its energy?

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.