Calculating Entropy Change in Niagara Falls Waterfall

In summary, the problem involves calculating the increase in entropy per second at Niagara Falls, given the amount of water falling and the distance it falls. The solution involves using the equation S = ∫ dQ/T and taking into account the constant temperature and negligible evaporation. The final step is to consider the conversion of potential energy to kinetic energy and then to heat energy to determine the change in entropy.
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XianForce
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Homework Statement


Every second at Niagara Falls, some 5.0 10^3 m3 of water falls a distance of 50.0 m. What is the increase in entropy per second due to the falling water? Assume that the mass of the surroundings is so great that its temperature and that of the water stay nearly constant at 20.0°C. Also assume a negligible amount of water evaporates.

Homework Equations



S = ∫ dQ/T

The Attempt at a Solution



Well, if I divided across by Δt, then I would have an equation set up for the quantity I need.

Temperature is constant, but since there is no real change in temperature or phase, is there any real change in heat? I'm not sure of where to go from here.

EDIT: Nevermind, I figured it out. Potential Energy converts to Kinetic Energy then to Heat Energy. Entropy is Q/T.
 
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so how do you solve this problem?
 

Related to Calculating Entropy Change in Niagara Falls Waterfall

1. What is the definition of "Rate of Change of Entropy"?

The rate of change of entropy is a measure of how quickly the entropy of a system is changing over time. It is calculated by dividing the change in entropy by the change in time.

2. How is the rate of change of entropy related to the second law of thermodynamics?

The second law of thermodynamics states that the total entropy of a closed system always increases over time. The rate of change of entropy reflects this by showing how much the entropy is increasing per unit of time.

3. What factors can affect the rate of change of entropy in a system?

The rate of change of entropy can be influenced by a variety of factors, including temperature, pressure, and chemical reactions. Any change in these factors can cause a change in the rate at which entropy is increasing or decreasing.

4. How is the rate of change of entropy measured in a physical system?

The rate of change of entropy can be measured using various methods, including calorimetry, which measures the heat flow in a system, or using mathematical equations that take into account the changes in temperature, pressure, and other variables.

5. What are some real-life examples of the rate of change of entropy?

Examples of the rate of change of entropy can be seen in everyday life, such as when an ice cube melts and the entropy of the water increases, or when a gas expands and cools, causing a decrease in entropy. It is also important in industrial processes, such as in power generation and chemical reactions.

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