A classroom that normally contains 40 people is tobe air-conditioned with window air-conditioning units of 5-kW cooling capacity. A person at rest may be assumed todissipate heat at a rate of about 360 kJ/h. There are 10 lightbulbs in the room, each with a rating of 100 W. The rate ofheat transfer to the classroom through the walls and the windows is estimated to be 15,000 kJ/h. If the room air is to bemaintained at a constant temperature of 21°C, determine the number of window air-conditioning units required

A classroom that normally contains 40 people is tobe air-conditioned with window air-conditioning units of 5-kW cooling capacity. A person at rest may be assumed todissipate heat at a rate of about 360 kJ/h. There are 10 lightbulbs in the room, each with a rating of 100 W. The rate ofheat transfer to the classroom through the walls and the windows is estimated to be 15,000 kJ/h. If the room air is to bemaintained at a constant temperature of 21°C, determine the number of window air-conditioning units required

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter2: Matter And Energy

Section: Chapter Questions

Problem 27RQ: How many Btu/h would be produced in a 12-kW electricheater?

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3. A classroom that normally contains 40 people is to be air-conditioned with window air-conditioning units of 5-kW cooling capacity. A person at rest may be assumed to dissipate heat at a rate of about 360 kJ/h. There are 10 light bulbs in the room, each with a rating of 100 W. The rate of heat transfer to the classroom through the walls and the windows is estimated to be 15,000 kJ/h. If the room air is to be maintained at a constant temperature of 210C, determine the number of window air-conditioning units required. draw a figure also, and explain each step by step solution.
An Air conditioned space is maintained at 26 deg DBT and 50% RH. When outside air conditions are 35 deg DBT and 28 deg WBT. If the space has a sensible heat gain of 17.6 kW and air is supplied to the room at a conditions of 8 deg saturated, calculate The specific volume rate of air supplied to the room 0.668 cubic metre /sec O 0.753 cubic metre /sec O 0.650 cubic metre /sec O 0.725 cubic metre /sec
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A classroom that normally contains 40 people is to be air-conditioned with window air-conditioning units of 5-kW cooling capacity. A person at rest may be assumed to dissipate heat at a rate of about 360kJ/h. There are 10 light bulbs in the room, each with a rating of 100W. The rate of heat transfer to the classroom through the walls and the windows is estimated to be 15,000kJ/h. If the room air is to be maintained at a constant temperature of 21°C, determine the number of window air-conditioning units required.
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