The impeller of a centrifugal fan is 320 mm in diameter and has backward curved blades. at a speed of 1460 rev/min the fan delivers 1,5 m3/s of air (rho = 1,2 kg/m3) against a total pressure of 350 pa. the manometric efficiency at this duty point is 60% and the whirl velocity at the impeller exit can be assumed to be twice the impeller peripheral velocity. taking the mechanical efficiency as 90%, calculate the power required to drive the fan

The second largest public utility in the nation is the sole provider of electricity in 32 counties of southern florida. to meet the monthly demand for electricity in these counties, which is given by the inverse demand function p = 1,200 – 4q, the utility company has set up two electric generating facilities: q1 kilowatts are produced at facility 1, and q2 kilowatts are produced at facility 2 (so q = q1 + q2). the costs of producing electricity at each facility are given by c1(q1) = 8,000 + 6q12 and c2(q2) = 6,000 + 3q22, respectively. determine the profit-maximizing amounts of electricity to produce at the two facilities, the optimal price, and the utility company’s profit