National Institute of Standards and Technology
Operating Principles of the NIST 4 Watt Balance Source
The watt balance lets researchers determine the mass of an object indirectly by determining two quantities: the strength of the magnetic field, and the current running through a coil of wire.
Bozeman Science
Gravitational Force
In this video Paul Andersen explains how an object with mass placed in a gravitational field experiences a gravitational force. On the Earth this gravitational force is known as weight. The gravitational force is equal to the product of...
Science Buddies
A Candle Seesaw Balancing Act
Do you love playing on a seesaw? Why is it that depending on where you sit on the beam, and the weight of the person on the other side, you either fly up into the air or fall down to the ground? And why is it so difficult to perfectly...
Learn French With Alexa
GCSE French Speaking: Any plans for Christmas?
In this video we look at this question: Qu’est-ce que tu vas faire pour célébrer Noël ? - What are you going to do to celebrate Christmas? (AQA Theme 1 - Identity and culture, Topic 4 - Customs and festivals in French-speaking...
Visual Learning Systems
Measuring Mass and Volume: Mass and Weight
This program begins by discussing common ways mass and volume are measured in the home. The video highlights how mass and volume are measured with various types of equipment in the school science lab. Some of the different tools used to...
Curated Video
Centre of Gravity: Finding the Balance Point of Irregular Objects
We use a plumb line and hook to find the centre of gravity of an irregularly shaped piece of card. A hole is punched in the card and it is suspended from the hook. A plumb line is used to let us draw the vertical line under the hole on...
TED Talks
Kristie Ebi: How climate change could make our food less nutritious
Rising carbon levels in the atmosphere can make plants grow faster, but there's another hidden consequence: they rob plants of the nutrients and vitamins we need to survive. In a talk about global food security, epidemiologist Kristie...
Curated Video
Why Do Tightrope Walkers Carry Long Poles when Walking on A Rope?
Carrying a pole helps the walker increase their rotational inertia, which aids in maintaining stability while walking over the narrow rope. The pole also adds more weight below the center of gravity of the walker, which is another bonus...
DoodleScience
Converging Lenses _ GCSE Physics
A lens is a piece of transparent material, like glass, that uses refraction to form an image by changing the direction of light. There are two types of lens; converging and diverging. Converging lenses are shown using this symbol. The...