Discuss the following scenarios related to the first law of thermodynamics: 1) On a hot summer day, a workshop employee turns his fan on when he leaves the room in the morning. When he returns in the evening, will the room be warmer or cooler than the neighbouring rooms? Why? Assume all the doors and windows are kept closed. ) A water pump that consumes 5 kW of electric power when operating is claimed to take in water from a lake and pump it to a pool whose free surface is 50 m above the free surface of the lake at a rate of 70 L/s. Determine if this claim is reasonable. :) A pump increases the pressure from 10 kPa to 70 kPa. Determine the power input required to pump 2 m³/s of water, given the inlet temperature of 15 °C. Does the inlet temperature have any significant effect on the required power?

Discuss the following scenarios related to the first law of thermodynamics: 1) On a hot summer day, a workshop employee turns his fan on when he leaves the room in the morning. When he returns in the evening, will the room be warmer or cooler than the neighbouring rooms? Why? Assume all the doors and windows are kept closed. ) A water pump that consumes 5 kW of electric power when operating is claimed to take in water from a lake and pump it to a pool whose free surface is 50 m above the free surface of the lake at a rate of 70 L/s. Determine if this claim is reasonable. :) A pump increases the pressure from 10 kPa to 70 kPa. Determine the power input required to pump 2 m³/s of water, given the inlet temperature of 15 °C. Does the inlet temperature have any significant effect on the required power?

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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