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Introduction to magnetism: Wikipedia article that provides an overview of the concept.

In this lesson you will learn about:

• The concept of magnetism
• Be able to identify magnetic and non-magnetic materials
• Identify properties and types of magnets
• Understand that metals can be magnetised and de-magnetised
• Understand that magnets have a magnetic field
• Understand that the Earth has a magnetic field

Forces at a distance are explained by fields (gravitational, electric, and magnetic) permeating space that can transfer energy through space. Magnets or electric currents cause magnetic fields; electric charges or changing magnetic fields cause electric fields.

Magnetism is an interaction that allows certain kinds of objects, which are called ‘magnetic’ objects, to exert forces on each other without physically touching. A magnetic object is surrounded by a magnetic ‘field’ that gets weaker as one moves further away from the object. A second object can feel a magnetic force from the first object because it feels the magnetic field of the first object. The further away the objects are the weaker the magnetic force will be.

Food webs are models that demonstrate how matter and energy is transferred between producers, consumers, and decomposers as the three groups interact within an ecosystem. Transfers of matter into and out of the physical environment occur at every level. Decomposers recycle nutrients from dead plant or animal matter back to the soil in terrestrial environments or to the water in aquatic environments. The atoms that make up the organisms in an ecosystem are cycled repeatedly between the living and nonliving parts of the ecosystem.

In this unit we will learn how these factors can affect the output of a simple machine. We will also learn about the difference between ideal mechanical advantage (IMA) and actual mechanical advantage (AMA), and how to apply your knowledge to calculate the efficiency of various simple machines.

An elaboration on how to use Newton's second law when dealing with multiple forces, forces in two dimensions, and diagonal forces.

An elaboration on some of the common misconceptions in dealing with Newton's Third Law. He also shows how to correctly and reliably identify Third Law force pairs.

This unit is about how things move along a straight line or, more scientifically, how things move in one dimension. Examples of this would be the movement (motion) of cars along a straight road or of trains along straight railway tracks.

In this lesson you will learn:

• to distinguish between distance and displacement
• to distinguish between speed and velocity
• understand acceleration
• interpret time-velocity graphs
• use equations of uniformly accelerated motion
• understand the concept of gravitational force