In this video Paul Andersen explains how waves interact when moving through one another. Unlike particles waves can interfere both constructively and destructively. The amount of interference is determined through the superposition...

You’re a vampire hunter entering the enemy’s lair. Can you outsmart this tricky brainteaser and vanquish the vampires? -- You’ve stealthily descended into the darkness of a vampire cave, setting a sequence of mirrors as you go. When...

In this video Paul Andersen explains how light can be absorbed, reflected, or transmitted as it moves from one medium to another. The reflection of different wavelengths creates the perceived color of an object. Absorbed light is...

In this video Paul Andersen compares and contrasts elastic and inelastic collisions. In all collisions the linear momentum will be conserved. In an elastic collision the kinetic energy of the objects will also be maintained. Several...

In this video Paul Andersen explains how light that is perfectly reflected creates specular reflection. The angle of the incident ray is equal to the angle of the reflected ray. Specular reflection is also known as mirror-like...

Paul Andersen introduces the concept of ethology and contrasts kinesis and taxis. He explains the importance of courtship rituals in fruit flies. He finally shows you how to use a choice chamber to study behavior in pill bugs.

SciShow explains how three important ingredients -- sunlight, water, and you -- interact to create the illusion of a rainbow. The colorful details are inside!

Have you ever put a seashell up to your ear and heard a roaring sound the sounds sort of like the ocean? Is it magic? No! It's science! Jessi and Squeaks explain what's up!

In this video Paul Andersen explains how simple harmonic motion occurs when a restoring force returns an object toward equilibrium. The two types of harmonic motion studied in AP Physics are the mass spring oscillator and the simple...

Howcast - Learn basic dance moves from choreographer Randy Connor in this Howcast dance video.

Howcast - Learn how to dance like Britney Spears from choreographer Randy Connor in this hip-hop dance video from Howcast.

Howcast - Learn how to do the Soulja Boy from choreographer Randy Connor in this hip-hop dance video from Howcast.

Howcast - Learn how to two-step from choreographer Randy Connor in this hip-hop dance video from Howcast.

Howcast - Learn the top two food photography tips from professional photographer Chris Ryan in this Howcast video.

Howcast - Let belly dancer Irina Akulenko teach you how to do the belly dance move known as the choo-choo shimmy in this Howcast video.

Howcast - Learn how to do the bouncing bread roll trick from professional illusionist Ben Nemzer in this Howcast magic tricks video.

Howcast - Learn how to do the b-boy toprock dance move the Indian step in this Howcast breakdancing tutorial with choreographer Victor "Kid Glyde" Alicea.

Howcast - Learn how to do a basic step-to-back dance move in this Howcast club dancing video with expert Tweetie.

Howcast - Learn how to do a neck catch basketball trick from the Harlem Wizards in this Howcast basketball video.

Howcast - Learn how to play an open or double stroke roll from drum teacher Jason Gianni in this Howcast drum video.

Howcast - Learn how to do the booty bounce dance move from fitness expert Rachel Warren in this hip-hop dance workout video from Howcast.

Howcast - Learn how to dance like Nsync in It's Gonna Be Me from Matt Lopez and DEF-C Crew in this hip-hop dance video, part five of a six-part Howcast series.

Howcast - Learn how to read a person's leg movements in this body language video from Howcast.

Howcast - Learn how to do pop diva dance moves for a cardio workout from fitness instructor Michelle Seabreeze in this Howcast dance workout video.