Seeing that the surface area to volume ratio of cells generally decreases as cells get larger, making the exchange of resources, waster and heat more and more difficult.
Surface tension in water, and how the surface tension is related to hydrogen bonding.
Introduction to Symbol Rate (Baud). Created by Brit Cruise.
The science of taxonomy and where humans fit into the tree of life.
Sophia shows how to display text on the canvas, plus change its size and color.
Sophia introduces the idea of "strings", then shows how to store strings in variables and display them using the text commands.
Theme and structure.
Intuition behind how heat gets transferred through thermal conduction.
Fire as thermal conduction, convection, and radiation.
Why metal at room temperature feels cooler than wood at room temperature.
Thermodynamics is the study of heat, "thermo," and work, "dynamics." We will be learning about energy transfer during chemical and physical changes, and how we can predict what kind of changes will occur. Concepts covered in this tutorial include the laws of thermodynamics, internal energy, heat, work, PV diagrams, enthalpy, Hess's law, entropy, and Gibbs free energy.
Intuition of how gases generate pressure in a container and why pressure x volume is proportional to the combined kinetic energy of the molecules in the volume. Created by Sal Khan.
To begin, Sal solves a constant temperature problem using PV=PV. Then he relates temperature to kinetic energy of a gas. In the second half of the video, he derives the ideal gas law. Created by Sal Khan.
Sal makes the case for the Kelvin scale of temperature and absolute zero by showing that temperature is proportional to kinetic energy. Then he explains that you need to use the Kelvin scale in the ideal gas law. To finish he does a sample ideal gas law problem. Created by Sal Khan.
Sal explains the concept of a mole. Then he derives the molar version of the ideal gas law PV=nRT, where the gas constant R=831 J/molK. Created by Sal Khan.
Sal uses the molar version of the ideal gas law to solve for the number of moles in a gas. He also shows how to convert this answer into number of molecules using Avogadro's number. Created by Sal Khan.
Thin film interference occurs when light waves reflecting off the top and bottom surfaces of a thin film interfere with one another. This type of interference is the reason that thin films, such as oil or soap bubbles, form colorful patterns. Created by David SantoPietro.
Let's work out a few details on how thin film interference works. Created by David SantoPietro.
Some examples of using the thin lens equation. Created by David SantoPietro.
Thomas Hunt Morgan's pioneering fruit fly work that helped validate the chromosomal theory of inheritance.