Written by Bel Richardson 

What is Physics 
The field of physics is
about understanding
matter and energy and
how they interact.


Matter is all things that take up space, which includes all liquids, solids, and gases. Energy is something that can be transferred between matter, like heat. Work happens when energy is transferred from one bit of matter to another. 
Do you think that light is matter or energy? 
Light is a form of energy. 


What is an atom? 
It is a unit of matter. Different elements have atoms with different structures. 
Understanding the structure of atoms has helped us to do amazing things. 


Some of these things, like bombs, have been destructive. Other research has revealed things about our universe and helped us to improve technology. 
All of these things are made up of atoms! 
Which of these are made up of atoms: your bones, water, our atmosphere? 


If physics is all about the ways that matter interacts and how energy transfers between matter, we need ways to record energy transfers and transformations. 
Why are time, mass, and distance important in physics? 


By observing time, mass, and distance in physics experiments, we can calculate the work that is done, the energy that is transferred, and how it transforms. 
What is the difference if you lift the first ball of Newton’s cradle a little or a lot? 


How far you lift the first ball changes the work that it can do and the energy that is transferred. If you lift the ball a little, it gently taps the others. If you lift it a lot, it sends the end ball flying. 


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