A fire starts in an apartment building in downtown Boston. When the firefighters arrive, they immediately get to work putting out the fire using a fire hose. The water for the fire hose is provided by a fire hydrant at ground level. Assume that the velocity of the liquid coming from the fire hydrant is 1.6 m/s, and that the pressure at the hose nozzle is atmospheric pressure (101000 Ра). a. The firefighters start with the ground floor, so there is no change in height between the fire hydrant and the hose nozzle. If the velocity of the water coming out of the nozzle is 12.8 m/s, find the pressure at the fire hydrant in units of Pa. b. After the ground floor fire is put out, another fire is spotted on another floor. A firefighter carrying the hose is lifted on a platform to the same height as the fire, which is 44.35 m above the ground. Assuming that the pressure found in part a) remains constant, what would be the new velocity of the water coming out of the nozzle at this new height?

A fire starts in an apartment building in downtown Boston. When the firefighters arrive, they immediately get to work putting out the fire using a fire hose. The water for the fire hose is provided by a fire hydrant at ground level. Assume that the velocity of the liquid coming from the fire hydrant is 1.6 m/s, and that the pressure at the hose nozzle is atmospheric pressure (101000 Ра). a. The firefighters start with the ground floor, so there is no change in height between the fire hydrant and the hose nozzle. If the velocity of the water coming out of the nozzle is 12.8 m/s, find the pressure at the fire hydrant in units of Pa. b. After the ground floor fire is put out, another fire is spotted on another floor. A firefighter carrying the hose is lifted on a platform to the same height as the fire, which is 44.35 m above the ground. Assuming that the pressure found in part a) remains constant, what would be the new velocity of the water coming out of the nozzle at this new height?

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

Chapter40: Typical Operating Conditions

Section: Chapter Questions

Problem 10RQ: The seasonal energy efficiency ratio (SEER) includes the energy used in the _____and _____cycles.

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