Earth's rotations and revolutions
These two short online tutorials discuss how the earth rotates and then the earth's revolutions.
These two short online tutorials discuss how the earth rotates and then the earth's revolutions.
In the first URL, the YouTube video explains why earth has spring, summer, autumn and winter seasons. The second URL summarizes the key takeaway points.
Introduction to passive and active transport
An elaboration on how to use Newton's second law when dealing with multiple forces, forces in two dimensions, and diagonal forces.
Newton's second law of motion is F = ma, or force is equal to mass times acceleration. Learn how to use the formula to calculate acceleration.
Osmosis is the movement of water across a semi-permeable membrane from an area of low solute concentration to an area of high solute concentration. Osmosis helps regulate the flow of water in and out of cells, which is crucial to their function.