This interactive addresses the question if we can reduce CO2 emissions by 20% of 1990 levels and help avoid dangerous climate change? Users of this interactive can manipulate changes to various sources and uses (supply and demand) of energy with the goal of reducing C02 emissions in Great Britain by 80% in the year 2050.

Created by David Lane of Rice University, this applet simulates experiments using 2 x 2 contingency tables. You specify the population proportions and the sample size and examine the effects on the probability of rejecting the null hypothesis. The author provides instructions and then five different exercises to practice these concepts. Overall, this is a nice interactive resource that allows users a more hands-on approach to statistics.

This simulation illustrates a wide range of 3D vector fields, including spherical, radial, and linear. The fields can be displayed as vectors, particle trajectories, equipotentials, and other options. The number of particles, vectors, or streamlines, and the field strength are adjustable. Directions and source code are also included. This is an extension of a 3D Electric and Magnetic Field viewer from the same author.

Solves for inductor and capacitor values for first, second, third and fourth order passive crossover systems for two way speaker systems. Includes Butterworth, Linkwitz-Riley, Bessel, Chebychev, Legendre, Gaussian and Linear-phase type calculations.

Solve various attributes of shapes and solids. Includes calculations for circle, parallelogram, rectangle, square, trapezoid, right circular cone, right circular cylinder, rectangular solid, and sphere geometric formulas. Geometry attributes include volume, area, perimeter, surface area, radius, length and circumference.

Online calculator for solving various interest related equations. Includes computations for compound interest, simple interest, annual percentage rate(APR) and regular deposits.

The electrical relationships between resistance (R), current (I), power (P) and voltage (E) is defined by Ohm's Law. One ohm is defined as the resistance which allow the current of one ampere under a potential difference of 1 volt.

Solve various attributes of different types of triangles. Triangle types include equilateral, isosceles, right and scalene. Attributes include sides, angles, altitudes, medians, angle bisectors, perimeters, semiperimeters, areas, radius of circumscribed circles, Pythagorean Theorem, radius of inscribed circles.

Acid-Base titration applet that plots pH changes as student adds acid or base. Gives choice of indicators (only two right now). Compares plots for titration of traditional solution and a buffered solution (several choices for comparison). Can alter starting concentrations.

In this outdoor game, learners play the roles of gray or red squirrels gathering and storing a supply of food in "fall" and recovering enough of them to survive the "winter." Learners carry bags representing their cheek pouches for carrying food. Learners investigate the advantages and disadvantages of how these two kinds of squirrels store food differently.

In this activity, learners simulate taking HIV antiretroviral drugs by using Tic Tac mints and Kool-Aid packets. Learners will experience firsthand how easy or difficult it is to fully adhere to a treatment program. Participation in this activity does not require eating or drinking anything and can accommodate learners with allergies.

In this activity, learners simulate Otto von Guericke's famous Magdeburg Hemispheres experiment. In this modern, low cost version, a pair of learners try to pull apart two suction cups (dent pullers). Learners then calculate the amount of force holding the dent pullers together.

The Materials Science and Technology Teacher's Workshop (MAST) provides this activity for classes learning about diodes and electrical currents. The laboratory illustrates how diodes can be used to rectify alternating current. It uses a galvanometer to determine the direction of current flow when an AC or DC current is applied to the circuit containing a diode in series with a resistor and a galvanometer.The lesson includes step by step directions for the experiment.The activity should require about 20-30 minutes of class time to complete. Discussion questions and teacher notes are included.

This module focuses on the basic concepts involved in dynamic electrochemistry when the net current is not zero - the combination of mass transfer and electrochemical reactions at the interface between solids and fluids. It is at an introductory level appropriate for undergraduates in their sophomore or junior years.