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→Work, Energy and Power
conversions in this section.
conversions in this section.
Some of the key ideas to be covered in this section are:
# Work has a physical meaning in relation to the force operating and this is linked to the concept of energy. Such work done can be measured in physical terms.
# Work has a physical meaning in relation to the force operating and this is linked to the concept of energy. Such work done can be measured in physical terms.
# What do we mean when we say an object has energy? We are introduced to the idea of kinetic and potential energy.
# What do we mean when we say an object has energy? We are introduced to the idea of kinetic and potential energy.
# Effectivesness of doing work is called power; work, energy and power have units of measure.
# Effectivesness of doing work is called power; work, energy and power have units of measure.<br><br>
== Concept flow ==
== Concept flow ==
energy is needed to do work. We will explore the idea of work done,
energy is needed to do work. We will explore the idea of work done,
energy, power and energy conversions in this section.
energy, power and energy conversions in this section.
Work always involves some opposing forces. What
Work always involves some opposing forces. What
This is true for any type of work.
This is true for any type of work.
Suppose that instead of lifting the box, we push
Suppose that instead of lifting the box, we push
it across a rough floor. In this case, we are not working against
it across a rough floor. In this case, we are not working against
that exists between the moving the box and the floor.
that exists between the moving the box and the floor.
In physical terms, work done is
In physical terms, work done is
directly proportional to both the applied force and the distance
directly proportional to both the applied force and the distance
and also to describe the energy content of food stuff.
and also to describe the energy content of food stuff.
= Energy in the world =
= Energy in the world =