In this video Paul Andersen explains how beats are created through interference of waves with similar frequencies. The changes in amplitude are caused by destructive and constructive interference. The frequency of beats is equal to the...

In this video Paul Andersen explains the important properties of solutions. A solution can be either a solid, liquid or gas but it must be homogeneous in nature. The solutes can not be separated with a filter and so either chromatography...

In this video Paul Andersen explains how thermal conductivity measures the ability of material to transfer heat from a hot to a cold object. The thermal conductivity of conductors is high because the heat travels through the delocalized...

In this video Paul Andersen explains how equilibrium is achieved in a reversible reaction. When the rate of the forward reaction is equal to the rate of the reverse reaction the system is at equilibrium. Graphical analysis of equilibrium...

In this video Paul Andersen explains how biodiversity measures the variety of genes, species, and ecosystems on the planet. Biodiversity provides resources and ecosystem services for humans on the planet. He also explains how...

In this video Paul Andersen describes motion as the movement of an object over time. Displacement, velocity and acceleration are all defined. An experiment in motion is used to calculate velocity and acceleration of a tennis ball.

In this video Paul Andersen defines the equilibrium constant (K) and explains how it can be calculated in various reversible reactions. The equilibrium constant is a ratio of the concentration of the products to the concentration of the...

In this video Paul Andersen defines the rate of a reaction as the number of reactants that are consumed during a given period of time. The rate of the reaction can be affected by the type of reaction as well as the concentration,...

In this video Paul Andersen explains how the enthalpy of a reaction can be released in an exothermic or consumed in an endothermic reaction. According to Hess's law if the reaction is reversed the sign of the enthalpy of reaction is also...

Paul Andersen explains how the rate law can be used to determined the speed of a reaction over time. Zeroth-order, first-order and second-order reactions are described as well as the overall rate law of a reaction. The rate of a reaction...

Paul Andersen describes the defining characteristics of the domain Eubacteria. He begins with a quick description of the phylogeny of bacteria and horizontal gene transfer. He then surveys the structures of a bacteria; nucleoid region,...

In this video Paul Andersen explains how mining is used to extract valuable minerals from the Earth's crust. Surface and subsurface mining are used to extract ore which is then processed. A discussion of ecosystem impacts and legislation...

Paul Andersen surveys the Kingdom Fungi. He starts with a brief description of the fungi phylogeny. He describes some of the major characteristics of fungi; heterotrophy, cell walls of chitin, hyphae, sessile. He describes the...

In this video Paul Andersen explains how a net torque acting on an object will create rotational motion. This motion can be described by the angular displacement, angular velocity, and angular acceleration. The linear velocity can be...

Paul Andersen shows you how to calculate the standard error of a data set. He starts by explaining the purpose of standard error in representing the precision of the data. The standard error is based on the standard deviation and the...

Paul Andersen explains the concept of coevolution. He begins with an analogy comparing the relationship of humans to technology with those of coevolving species. He then discriminates between coevolution and convergent evolution. He...

Paul Andersen explains the process of anaerobic respiration. This process involves glycolysis and fermentation and allows organisms to survive without oxygen. Lactic acid fermentation is used in animals and bacteria and uses lactate as...

Paul Andersen shows you how to graph data by hand. He explains the required elements of a scatter plot with a best fit line. He shows you how to properly scale and label the axes.

In this video Paul Andersen explains how light can be treated as both a particle and a wave. Physicists use scale to determine which model to use when studying light. When the wavelength of light is equivalent to the size of the object a...

In this video Paul Andersen explains how gases differ from the other phases of matter. An ideal gas is a model that allows scientists to predict the movement of gas under varying pressure, temperature and volume. A description of both...

Paul Andersen explains how organisms are able to regulate their internal body temperature (or not). He starts with a brief description conduction, convection, radiation and metabolism. He contrasts ectotherms and endotherms. He also...

Paul Andersen discusses the specifics of phylogenetics. The evolutionary relationships of organisms are discovered through both morphological and molecular data. A specific type of phylogenetic tree, the cladogram, is also covered.

Paul Andersen explains how paraffin vapor combusts in a candle. He also describes energy and mass conversion and almost burns himself.

Mr. Andersen shows you how to sink leaf chads in preparation for the AP Biology photosynthesis lab. An empty syringe is used to remove gas from the leaves before the lab. As the chloroplasts absorb light they produce oxygen bubbles which...