Watch alpha particles escape from a polonium nucleus, causing radioactive alpha decay. See how random decay times relate to the half life.
This article lists common misconceptions about light, heat, and the sun. It provides formative assessment probes and information about teaching for conceptual change.
The author explains heat transfer and how it applies to living in extremely cold environments.
This article aligns the concepts of Essential Principle 2 of the Climate Sciences to the K-5 content standards of the National Science Education Standards. The author also identifies common misconceptions about heat and the greenhouse gases effect and offers resources for assessing students' understanding of interactions among components of the Earth system. This article continues the examination of the climate sciences and climate literacy on which the online magazine Beyond Weather and the Water Cycle is structured.
How much radiation are we exposed to every day? Find out in this video segment adapted from FRONTLINE.
How do greenhouse gases affect the climate? Explore the atmosphere during the ice age and today. What happens when you add clouds? Change the greenhouse gas concentration and see how the temperature changes. Then compare to the effect of glass panes. Zoom in and see how light interacts with molecules. Do all atmospheric gases contribute to the greenhouse effect?
Students model the rate of radioactive changes with pennies and then dice, constructing graphs and finding the half-life of their two “radioactive isotopes”.
Earl Ubell is a pioneer among science and health writers in America. After a long, distinguished career at The New York Herald Tribune from 1943 to 1966, he went on to work at both CBS and NBC News. Prominent in the emerging scientific writing community in the 1950s and early 1960s, he was a recipient of the Lasker Medical Journalism Award 1957. Milton Stanley Livingston was a leading physicist in the field of magnetic resonance accelerators. Working first with professor Ernest O. Lawrence at the University of California, Livingston was instrumental in the development of the Berkeley cyclotron. Moving to Cornell in 1938, Livingston was part of the core group who established nuclear physics as a field of study. Choosing to stay with the Cornell cyclotron rather than follow colleagues onto the Manhattan Project, Livingston was involved in the production of radioisotopes for medical purposes. At the time of this interview, Livingston was director of the Cambridge Electron Accelerator, a joint project of Harvard University and MIT.In this program segment Louis Lyons quizzes Earl Ubell about the lack of public knowledge and the perception of the nuclear bomb, while pressing Professor Livingston to explain exactly what nuclear fallout is, and the danger it presents.
Create a laser by pumping the chamber with a photon beam. Manage the energy states of the laser's atoms to control its output.
Create a laser by pumping the chamber with a photon beam. Manage the energy states of the laser's atoms to control its output.
How do microwaves heat up your coffee? Adjust the frequency and amplitude of microwaves. Watch water molecules rotating and bouncing around. View the microwave field as a wave, a single line of vectors, or the entire field.
How do microwaves heat up your coffee? Adjust the frequency and amplitude of microwaves. Watch water molecules rotating and bouncing around. View the microwave field as a wave, a single line of vectors, or the entire field.
Heat is distributed via radiation, which is the transfer of energy waves.
Produce light by bombarding atoms with electrons. See how the characteristic spectra of different elements are produced, and configure your own element's energy states to produce light of different colors.
Explore an active area of research in optical physics: producing designer pulse shapes to achieve specific purposes, such as breaking apart a molecule. Carefully create the perfect shaped pulse to break apart a molecule by individually manipulating the colors of light that make up a pulse.
The electric field lines from a point charge evolve in time as the charge moves. Watch radiation propagate outward at the speed of light as you wiggle the charge. Stop a moving charge to see bremsstrahlung (braking) radiation. Explore the radiation patterns as the charge moves with sinusoidal, circular, or linear motion. You can move the charge any way you like, as long as you don’t exceed the speed of light.
Broadcast radio waves from KPhET. Wiggle the transmitter electron manually or have it oscillate automatically. Display the field as a curve or vectors. The strip chart shows the electron positions at the transmitter and at the receiver.
Broadcast radio waves from KPhET. Wiggle the transmitter electron manually or have it oscillate automatically. Display the field as a curve or vectors. The strip chart shows the electron positions at the transmitter and at the receiver.
Learn about different types of radiometric dating, such as carbon dating. Understand how decay and half life work to enable radiometric dating to work. Play a game that tests your ability to match the percentage of the dating element that remains to the age of the object.
This article describes the energy that radiates from the sun, the concept of albedo, Earth's radiation budget, and the effect of decreasing albedo on Earth's climate.