Download Physical Science

Next Generation Science Standards: Middle School
Physical Science
1. Matter & Its Interactions
a. Structure & Properties
i. What’s an atom?
ii. What’s a molecule?
iii. What holds a molecule together?
iv. What are physical and chemical properties? Examples? Can you change
them?
v. What about solid/liquid/gas? How do you change between them? What’s
heat got to do with it? Do the properties change if you change state?
vi. Heat vs. temperature
b. Chemical Reactions
i. A reaction is different from a change of phase (solid/liquid) in that the
molecules are rearranged so that they have a different arrangement than
what you started with. This gives you new properties.
ii. Mass is conserved in all reactions.
2. Motion & Stability: Forces & Interactions
a. Forces & Motion
i. Mechanics is the part of physics that studies motion and the causes of
motion. You can measure things about motion, like velocity and
acceleration.
ii. What causes motion? An unbalanced force. An unbalanced force can
also deform something. (A smashed pear.) Look at forces, push/pull on
box. If you have two balanced forces—I push a box with the same force
that you push a box, and you are on the opposite side of the box—the
box doesn’t move. They cancel each other.
iii. Two kinds of forces: contact and non-contact. (Non-contact are gravity,
electromagnetic force). Non-contact forces impact motion through
fields.
iv. Force has a direction.
v. Newton’s three laws.
b. Types of Interactions
i. Gravity. Always attractive, never repulsive. What does gravity depend
on? The mass of the two things and distance between them.
ii. Electromagnetic. Can be attractive or repulsive. Depends on distance,
charge.
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3. Energy
a. Definitions of Energy
i. Kinetic energy, energy of motion
ii. Potential energy, energy due to position. This is stored energy.
iii. How is heat related to energy? Heat is the transfer of energy into an
object that make the object’s molecules move more rapidly—heat
increases the KE of the molecules.
b. Conservation of Energy & Energy Transfer
i. Energy is always conserved
ii. How could you transfer energy? You can lift a rock and put it on the
shelf—you would be giving it PE. You can kick a ball—you could be
giving it KE. You use force to transfer energy.
c. Relationship Between Energy and Forces
i. Energy is a property of a thing. You can measure it. You can measure
the energy of a moving ball. But force explains how this ball got this
energy. Energy alone doesn’t explain anything. Force can explain why
the object is moving at that speed, in that direction. You can transfer
energy into an object by applying a force to it.
d. Energy in Chemical Process and Everyday Life
4. Waves & Their Applications in Technologies
a. Wave Properties
i. Forces can also cause waves, like if you pluck a guitar string. A wave is a
disturbance or vibration that moves through space. First the string
vibrates and then the string causes the air molecules to vibrate. This
disturbance moves through the air molecules and some of it hits your
eardrum, and that’s how we hear.
ii. A wave is the transfer of energy, but NOT a transfer of mass. A mass
might vibrate but it doesn’t not in the end change its position—after the
wave passes through it, the mass is in the same spot.
iii. Mechanical waves require a medium, like air molecules or water
molecules or a rope or Slinky. There are also waves that don’t require a
medium, like light waves. These waves can travel through a vacuum. The
energy in this kind of waves moves through the vibration of fields.
iv. Wavelength, amplitude, and frequency are ways to measure a wave.
v. Bigger amplitude means that there is more energy in this wave.
b. Electromagnetic Radiation
i. Light waves don’t go through a medium. The vibrate fields.
ii. If light waves go through matter, they can be reflected, absorbed, or
transmitted through the matter.
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