A Camper Carries Her Drinks in an Ice Chest Made

question 91

Multiple Choice

A camper carries her drinks in an ice chest made of styrofoam. The chest is 40 cm × 45 cm × 70 cm, and the walls and lid are 2.5 cm thick. The contents of the chest are ice, water, cans of soft drinks, and other food, all of which are in thermal equilibrium with the ice water. The temperature just outside the ice chest is 35°C. What is the rate of heat flow through the walls of the box? The thermal conductivity of styrofoam is 0.010 W/(m·K) .

• A) 14 W
• B) 16 W
• C) 18 W
• D) 20 W
• E) 22 W

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Definitions:

Non-REM Sleep

A phase of sleep that is divided into three stages and does not include rapid eye movement, responsible for deep and restorative sleep.

Sleepwalking

A phenomenon where an individual walks or performs other complex behaviors while in a state of sleep.

Early Childhood

A developmental period in human growth from birth to eight years of age, focusing on the physical, cognitive, and emotional development of children.

Deepest Stage

Often referring to the fourth stage of non-REM sleep, characterized by slow brain waves and the deepest level of sleep, crucial for restorative functions.