what happens to a room temperature if a 0.25 KW fan is left running inside it for 24 hrs with doors and windows closed? Explain.
what happens to a room temperature if a 0.25 KW fan is left running inside it...
3. A student living in a 4-m X 6-m X 6-m dormitory room turns on her 150-W fan before she leaves the room on a summer day, hoping that the room will be cooler when she comes back in the evening. Assuming all the doors and win- dows are tightly closed and disregarding any heat trans- fer through the walls and the windows, determine the tem- perature in the room when she comes back 10 h later. Use specific heat...
What is the value of Kw for a sample of pure water at room temperature? • Write your answer in scientific notation. Use the multiplication symbol rather than the letter at in your answer. destina
A room with a heat loss of 3 kW through walls and windows has to be kept at 20 degree C. A radiator of area 6m^2 is used to heat the room. If the heat transfer coefficient is 5W.K^-1 .m^-2 what would be the correct temperature of the radiator? 0 degree C 20 degree C 80 degree C 100 degree C
On a winter day with a temperature of Tc, the temperature inside a room is Th, where Th > Tc. The heat conduction rate through a slab of thickness L, surface area A, thermal conductivity k is measured to be H. Assume you found a way to triple the slab thickness and reduce the thermal conductivity to one quarter, what is the new heat transfer rate H’ in terms of H? Assume the temperatures inside and outside the room and...
You are inside a room, 15 m from the west wall, and centered between two open doors (like slits) that are 3 m apart on the west wall. Someone is blaring a 200 Hz tone outside the room so that it enters the doors as a plane wave. You hear a maximum intensity in your current position. As you walk (north) along the direction of the west wall with the doors (but maintain a distance 15 m from the wall),...
7 When a 1.5'x3' window is open, the sound-intensity-level of the street's pois inside the room is 60 dB. When the window is closed, it blocks all the street's noise. (a) What would be the noise-intensity-level inside the room when the window is left slightly open, so that the open area is 18 square inch? (b) What would be the street's noise-intensity-level when the window is open to 18 square inches, if when the window is completely closed the street...
A summer air conditioning system with recirculating air stream and BPF = 0 has a room sensible heat load of 20 kW and a room latent heat load of 2.22 kW. The required inside conditions are 22°C and 50% RH, and the outdoor design conditions are 36°C and 60% RH. The mass flow rate of the outside air is 15% of the mass flow rate of the supply air. Find a) RSHF b) the point s on the chart, mass...
Assuming a section of insulation as below, what is the inside wall temperature for the figure below? The temperature on the outside is 1000°C, and the heat transfer 4 kW/m. It can be assumed that convection effects are small and can be ignored. a) Calculate the temperature assuming surfaces normal to the direction of heat flow are b) Calculate the temperature assuming that the surfaces parallel to heat flow are adiabatic. c) isothermal. Give your answer to the nearest degree...
If a bottle of vinegar is left open to the air (room temperature) for a month, what would happen to the pH of the vinegar?
6. An office building requires a heat transfer rate of 20 kW to maintain the inside temperature at 21°C when the outside temperature is 0°C. A vapor-compression heat pump with Refrigerant 134a as the working fluid is to be used to provide the necessary heating. The compressor operates adiabatically with an isentropic efficiency of 82%. Specify appropriate evaporator and condenser pressures of a cycle for this purpose assuming Δ1cond-Al evap-10°C, as shown below. The states are numbered as shown below....