A certain diet doctor encourages people to diet by drinking...

A certain diet doctor encourages people to diet by drinking ice water. His theory is that the body must burn off enough fat to raise the temperature of the water from $0.00^{\circ} \mathrm{C}$ to the body temperature of $37.0^{\circ} \mathrm{C}$ How many liters of ice water would have to be consumed to burn off $454 \mathrm{~g}$ (about 1 lb) of fat, assuming that burning this much fat requires 3900 Cal be transferred to the ice water? Why is it not advisable to follow this diet? (One liter $=10^{3} \mathrm{~cm}^{3}$. The density of water is $1.00 \mathrm{~g} / \mathrm{cm}^{3}$.)

Labs

Want to see this concept in action?

NEW

Explore this concept interactively to see how it behaves as you change inputs.

View Labs

Key Concepts

Energy Balance and Physiological Considerations

This concept involves understanding that even though external actions (like drinking ice water) can lead to an increase in energy expenditure due to warming the water, the actual amount of energy burned is minimal compared to the energy intake from food. Additionally, the human body is finely tuned to regulate its temperature, and relying on such methods for weight loss can be ineffective or even harmful to health.

Specific Heat Capacity

This is a property of a material that indicates how much energy is required to raise one unit of mass by one degree Celsius. For water, which has a specific heat capacity of about 1 calorie/gram°C, this concept is crucial for calculating the energy absorbed as water warms from one temperature to another.

Unit Conversion and Energy Calculations

Accurate problem-solving in thermodynamics involves converting units appropriately and applying the relationship Q = m·c·?T. This means converting between units such as liters to grams (using the density of water) and correctly applying energy units (Calories, which in this context are nutritional calories) to determine how much water is needed to absorb a given amount of energy.

Transcript

Please give Ace some feedback