A room is initially at the same temperature as the air outdoors, 10°C. A heater whichconsumes 1kW of electricity is switched on inside the room. If the exposed surfacearea of the room is 30m^2 and the convection heat transfer coefficient from theoutside of the room to the surroundings is 6 W/m^2.°C, calculate the equilibriumtemperature reached in the room, assuming that the heater is 95% efficient. Neglectany heat transfer out of the room by conduction and radiation

The intermal energy of a thermodynamic system decreases by 435 kJ. If at the same time, 164 kJ of work is done on the system, find the heat transfer. Answer:

You have three devices: a Carnot heat engine, a Carnot heat pump and a Carnot refrigerator. Use a cold reservoir temperature of -18C. Plot the heat engine Carnot efficiency, the COPrefrig, and the COPhp as a function of the hot reservoir temperature from 27C to 177C. Use temperature increments of 5K in your plot. Make sure and reference a previous slide 'how to make a plot' that gives you the key elements of making a graph (in your choice of software). Describe what you see. Also describe the illustrated relationship between COPhp and COPref.

Two Carnot heat engines run in series with the efficiency of first engine is k times the second. If the thermal reservoir at low and high temperatures were denoted by TL and TH, find the simplified ratio of heat absorbed to heat rejected by the second heat engine in terms of TL, TH and k only.

An electric home stove with 3 burners and microwave is used in preparing a meal asfollows. Burner 1: 20 minutes Burner 2: 40 minutes Burner 3: 15 minutes . Microwave: 30minutes. If each burner is rated at 1.2 kW and the oven at 1.8 kW, and electricity costs 1000(IQ =Iraqi Dinar) per k Wh, calculate the cost of electricity used in preparing the meal?

A household refrigerator is maintained at a temperature of 2 degrees C. Every time the door is opened, warm material is placed inside introducing an average of 420 kJ, but making only a small.change in the temperature of the refrigerator. The door is opened 20 times a day and the refrigerator operates at -15% of the Ideal COP. The cost of the work is 4 rupees per kWh. What is the monthly bill for this refrigerator? The atmosphere is at 30 degrees C

Please answer it step by step solution. Topic : Thermodynamics

imagine a heat machine that operates between two thermal reservoir T1<T2 ,the machine does a work in quantity W,and it exchange heat in quantity Q1 and Q2 with its reservoirs.( Note:  this heat machine dose not have to be a carnot machine , only requirement is that it must be cyclical).under this circumstances,if the work is positive,prove that Q2>0 and Q1>0.

Please give right answer A carnot engine receives 1000Btu of heat from a heat reservoir at an unknown temperature and rejects 400 Btu of heat to a low temperature reservoir at 77oF. Determine the high temperature

H6. An air conditioner in an upper-floor apartment unit is turned on during a hot summer afternoon. If heat can be removed from the interior at a rate of 1.5 kW, estimate the time required to cool the air inside the apartment to its final temperature. Your estimate should create any needed input data and should incorporate factors like the size of the apartment and the behavior of air.