The Second Law of Thermodynamics

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Entropy: The Second Law of Thermodynamics
Turn to an idea that has been compared to a work of Shakespeare: the second law of thermodynamics. According to the second law, entropy, a measure of disorder, always increases in a closed system. Order can only increase at the cost of even greater entropy elsewhere in the system.
Entropy and Microstate Information
Return to the concept of entropy, tracing its origin to thermodynamics, the branch of science dealing with heat. Discover that here the laws of nature and information meet. Understand the influential second law of thermodynamics, and conduct a famous thought experiment called Maxwell's demon.
Complexity and Life
Discover that Maxwell's demon from episode 10 provides the key to understanding how complexity and life can exist in a universe in which entropy is increasing. Consider how life is not only compatible with, but is an outgrowth of, the second law of thermodynamics and the arrow of time.
Erasure Cost and Reversible Computing
Maxwell's demon has startling implications for the push toward ever-faster computers. Probe the connection between the second law of thermodynamics and the erasure of information, which turns out to be a practical barrier to computer processing speed. Learn how computer scientists deal with the demon.
Consequences of the Second Law
The second law puts limits on the efficiency of heat engines and shows that humankind's energy use could be better planned. Learn why it makes sense to exploit low-entropy, high-quality energy for uses such as transportation, motors, and electronics, while using high-entropy random thermal energy for heating.
Heat and Work
The first law of thermodynamics relates the internal energy of a system to the exchange of heat and mechanical work. Focus on isothermal (constant temperature) and adiabatic (no heat flow) processes, and see how they apply to diesel engines and the atmosphere.
Entropy and Counting
After establishing in previous episodes that the arrow of time must be due to entropy, begin a deep exploration of this phenomenon. In the 1870s, physicist Ludwig Boltzmann proposed a definition of entropy that explains why it increases toward the future. Analyze this idea in detail.
The Ideal Gas
Delve into the deep link between thermodynamics, which looks at heat on the macroscopic scale, and statistical mechanics, which views it on the molecular level. Your starting point is the ideal gas law, which approximates the behavior of many gases, showing how temperature, pressure, and volume are connected by a…
Rotational Motion
Turn your attention to rotational motion. Rotational analogs of acceleration, force, and mass obey a law related to Newton's second law. This leads to the concept of angular momentum and the all-important -conservation of angular momentum, which explains some surprising and seemingly counterintuitive phenomena involving rotating objects.
Using Newton's Laws: 1-D motion
Investigate Newton's second law, which relates force, mass, and acceleration. Focus on gravity, which results in a force, called weight, that's proportional to an object's mass. Then take a ride in an elevator to see how your measured weight changes due to acceleration during ascent and descent.
Playing with Entropy
Sharpen your understanding of entropy by examining different macroscopic systems and asking, which has higher entropy and which has lower entropy? Also evaluate James Clerk Maxwell's famous thought experiment about a demon who seemingly defies the principle that entropy always increases.
Colliding Particles
Once physicists established the need for the Higgs boson to exist, how did they set out to locate it? It was just a matter of bringing the particles and fields together under the right conditions. You'll see how physicists use Feynman diagrams to keep track of how virtual particles carry…