An Engineer Wants to Use a River (Minimum Temperature of 4°C)

question 21

Multiple Choice

An engineer wants to use a river (minimum temperature of 4°C) to cool his electrical plant, which heats water with a boiler operating at 220°C. If he wishes to produce 185 kW of power using this plant, what is the minimum power he must supply to his boiler if it is maximally efficient?

• A) 233 kW
• B) 187 kW
• C) 332 kW
• D) 422 kW

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Definitions:

Sound Frequency

The number of sound vibrations per second, measured in hertz (Hz), affecting the pitch of the sound.

Crickets

Insects of the order Orthoptera, known for the chirping sound males make by rubbing their wings together, often associated with summer nights.

Ultrasonic Bat Calls

High-frequency sound waves emitted by bats for navigation and locating prey, inaudible to most other species.

Intensity Threshold

The minimum level of stimulus intensity required to trigger a detectable response or reaction.