Dope the semiconductor to create a diode. Watch the electrons change position and energy.
Why do the lights turn on in a room as soon as you flip a switch? Flip the switch and electrons slowly creep along a wire. The light turns on when the signal reaches it.
Why do the lights turn on in a room as soon as you flip a switch? Flip the switch and electrons slowly creep along a wire. The light turns on when the signal reaches it.
Is it a tumor? Magnetic Resonance Imaging (MRI) can tell. Your head is full of tiny radio transmitters (the nuclear spins of the hydrogen nuclei of your water molecules). In an MRI unit, these little radios can be made to broadcast their positions, giving a detailed picture of the inside of your head.
Build coin expressions, then exchange them for variable expressions. Simplify and evaluate expressions until you are ready to test your understanding of equivalent expressions in the game!
This simulation lets you see sound waves. Adjust the frequency or volume and you can see and hear how the wave changes. Move the listener around and hear what she hears.
This simulation lets you see sound waves. Adjust the frequency or volume and you can see and hear how the wave changes. Move the listener around and hear what she hears.
Have you ever wondered what happens to the different stars in the night sky as they get older? The Star in a Box application lets you explore the life cycle of stars. It animates stars with different starting masses as they change during their lives. Some stars live fast-paced, dramatic lives; others change very little for billions of years. The app visualises the changes in mass, size, brightness and temperature for all these different stages.
Watch different types of molecules form a solid, liquid, or gas. Add or remove heat and watch the phase change. Change the temperature or volume of a container and see a pressure-temperature diagram respond in real time. Relate the interaction potential to the forces between molecules.
Watch different types of molecules form a solid, liquid, or gas. Add or remove heat and watch the phase change. Change the temperature or volume of a container and see a pressure-temperature diagram respond in real time. Relate the interaction potential to the forces between molecules.
Heat, cool and compress atoms and molecules and watch as they change between solid, liquid and gas phases.
The classic Stern-Gerlach Experiment shows that atoms have a property called spin. Spin is a kind of intrinsic angular momentum, which has no classical counterpart. When the z-component of the spin is measured, one always gets one of two values: spin up or spin down.
Explore stretching just a single strand of DNA using optical tweezers or fluid flow. Experiment with the forces involved and measure the relationship between the stretched DNA length and the force required to keep it stretched. Is DNA more like a rope or like a spring?
Explore stretching just a single strand of DNA using optical tweezers or fluid flow. Experiment with the forces involved and measure the relationship between the stretched DNA length and the force required to keep it stretched. Is DNA more like a rope or like a spring?
What happens when sugar and salt are added to water? Pour in sugar, shake in salt, and evaporate water to see the effects on concentration and conductivity. Zoom in to see how different sugar and salt compounds dissolve. Zoom in again to explore the role of water.
Explore what it means for a mathematical statement to be balanced or unbalanced by interacting with integers and variables on a balance. Find multiple ways to balance x and y to build a system of equations.
Investigate how torque causes an object to rotate. Discover the relationships between angular acceleration, moment of inertia, angular momentum and torque.
Investigate how torque causes an object to rotate. Discover the relationships between angular acceleration, moment of inertia, angular momentum and torque.
This activity aims to stimulate discussion on the question of whether computers can exhibit Ňintelligence" or are ever likely to do so in the future. Learners play a game and try to distinguish between a human and a computer by asking questions and analyzing the answers. This game is similar to the Turing Test, founded by British mathematician Alan Turing. Variations, extensions, background information and further reading suggestions are included in the PDF.
Explore pressure under and above water. See how pressure changes as you change fluids, gravity, container shapes, and volume.