A heating system must maintain the interior of a building at TH = 20°C when the outside temperature is TC = 10°C. If the rate of heat transfer from the building through its walls and roof is 15 kW, determine the electrical power required, in kW, to heat the building using: (a) electrical-resistance heating; (b) a heat pump whose coefficient of performance is 4; (c) a reversible heat pump operating between hot and cold reservoirs at 20°C and 10°C, respectively.

When at a point two solid phase changes to one solid phase on cooling then it is known as a) eutectoid point b) eutectic point c) peritectic point d) peritectoid point

Line joining liquid phase with liquid and solid phase mixture is known as: a) liquidus b) solidus c) tie line d) none of the mentioned

Ajournal bearing has a journal diameter of 3.250 in with a unilateral tolerance of 20.003 in. the bushing bore has a diameter of 3.256 in and a unilateral tolerance of 0.004 in. the bushing is 2.8 in long and supports a 700-lbf load. the journal speed is 900 rev/min. find the minimum oil film thickness and the maximum film pressure for both sae 20 and sae 20w-30 lubricants, for the tightest assembly if the operating film temperature is 160°f. a computer code is appropriate for solving this problem.