This video segment adapted from the Space Telescope Science Institute shows what the Hubble telescope found when it stared at a single, nearly empty spot in the sky for 10 days in 1995.

Check out this ping pong ball explosion demonstration which happens as a result of liquid nitrogen expanding quickly. [4:14]

Learn how dark energy accelerates the expansion of space. Find out about the theory that the universe will expand indefinitely and faster all the time. [11:22]

Learn that the area under a curve can help you find the work done! This video lecture explains why a pressure vs. volume graph could be used to find the work either on or by the system. The video does not go through the calculus of how...

In this cool science experiment, you will see how you can put a balloon directly into a candle flame and the balloon will not burst. The power of heat conduction makes this possible. Have fun while learning about heat transfer and energy...

Economists typically focus on three kinds of unemployment: cyclical, frictional, and structural. Learn about them, and how they relate to the business cycle, in this video. [5:38]

Watch a "Pharaoh's Serpent" reaction, which occurs during the combustion of mercury thiocyanate. [0:36]

In this lesson, students will learn Area: Using Expansion and Distribution. Student watch a video tutorial.