• Students know a force has both direction and magnitude.
• Students know when an object is subject to two or more forces at once, the result is the cumulative effect of all the forces.
• Students know when the forces on an object are balanced, the motion of the object does not change.
• Students know how to identify separately the two or more forces that are acting on a single static object, including gravity, elastic forces due to tension or compression in matter, and friction.
• Students know that when the forces on an object are unbalanced, the object will change its velocity (that is, it will speed up, slow down, or change direction).
• Students know the structure of the atom and know it is composed of protons, neutrons, and electrons.
• Students know that in solids the atoms are closely locked in position and can only vibrate; in liquids the atoms and molecules are more loosely connected and can collide with and move past one another; and in gases the atoms and molecules are free to move independently, colliding frequently.
• Students know how to predict the voltage or current in simple direct current (DC) electric circuits constructed from batteries, wires, resistors, and capacitors.
• Students know how to solve problems involving Ohm's law.
• Students know any resistive element in a DC circuit dissipates energy, which heats the resistor. Students can calculate the power (rate of energy dissipation) in any resistive circuit element by using the formula Power = IR (potential difference) x I (current) = 1² R.
• Students know the properties of transistors and the role of transistors in electric circuits.
• Students know charged particles are sources of electric fields and are subject to the forces of the electric fields from other charges.
• Students know magnetic materials and electric currents (moving electric charges) are sources of magnetic fields and are subject to forces arising from the magnetic fields of other sources.
• Students know how to determine the direction of a magnetic field produced by a current flowing in a straight wire or in a coil.
• Students know changing magnetic fields produce electric fields, thereby inducing currents in nearby conductors.
• Students know plasmas, the fourth state of matter, contain ions or free electrons or both and conduct electricity.
• Students know electric and magnetic fields contain energy and act as vector force fields.
• Students know the force on a charged particle in an electric field is qE, where E is the electric field at the position of the particle and q is the charge of the particle.
• Students know how to calculate the electric field resulting from a point charge.
• Students know static electric fields have as their source some arrangement of electric charges.
• Students know the magnitude of the force on a moving particle (with charge q) in a magnetic field is qvB sin(a), where a is the angle between v and B (v and B are the magnitudes of vectors v and B, respectively), and students use the right-hand rule to find the direction of this force.
• Students know how to apply the concepts of electrical and gravitational potential energy to solve problems involving conservation of energy.
• describes and compares the properties of particles and waves.
• knows the general properties of the atom (a massive nucleus of neutral neutrons and positive protons surrounded by a cloud of negative electrons) and accepts that single atoms are not visible.
• knows that radiation, light, and heat are forms of energy used to cook food, treat diseases, and provide energy.
• knows that many forces (e.g., gravitational, electrical, and magnetic) act at a distance (i.e., without contact).
• knows common contact forces.
• knows that if more than one force acts on an object, then the forces can reinforce or cancel each other, depending on their direction and magnitude.
• Some forces act through physical contact, while others act at a distance.
• Investigate and describe types of forces including contact forces and forces acting at a distance, such as electrical, magnetic, and gravitational.
• Investigate and describe that an unbalanced force acting on an object changes its speed, or direction of motion, or both.
• Explore the scientific theory of atoms (also known as atomic theory) by using models to explain the motion of particles in solids, liquids, and gases.
• Classify and compare substances on the basis of characteristic physical properties that can be demonstrated or measured; for example, density, thermal or electrical conductivity, solubility, magnetic properties, melting and boiling points, and know that these properties are independent of the amount of the sample.
• Explore the scientific theory of atoms (also known as atomic theory) by recognizing that atoms are the smallest unit of an element and are composed of sub-atomic particles (electrons surrounding a nucleus containing protons and neutrons).
• Matter can undergo a variety of changes.
• analyze energy conversions such as those from radiant, nuclear, and geothermal sources; fossil fuels such as coal, gas, oil; and the movement of water or wind; and