Facts:

• When work is done on or by a system, there is a change in the total energy of the system.

• Work done against friction results in an increase in the internal energy of the system.

• Power is the time-rate at which work is done or energy is expended.

• All energy transfers are governed by the law of conservation of energy.

• Energy may be converted among mechanical, electromagnetic, nuclear, and thermal forms.

• Potential energy is the energy an object possesses by virtue of its position or condition. Types of potential energy are gravitational and elastic.

• Kinetic energy is the energy an object possesses by virtue of its motion.

• In an ideal mechanical system, the sum of the macroscopic kinetic and potential energies (mechanical energy) is constant.

• In a nonideal mechanical system, as mechanical energy decreases there is a corresponding increase in other energies such as internal energy.

Facts:

• The inverse square law applies to electrical and gravitational fields produced by point sources.

• The factors affecting resistance in a conductor are length, cross-sectional area, temperature, and resistivity.

• All materials display a range of conductivity. At constant temperature, common metallic conductors obey Ohm’s Law.

• Moving electric charges produce magnetic fields. The relative motion between a conductor and a magnetic field may produce a potential difference in the conductor.

• An oscillating system produces waves. The nature of the system determines the type of wave produced.

• Waves carry energy and information without transferring mass. This energy may be carried by pulses or periodic waves.

• Waves are categorized by the direction in which particles in a medium vibrate about an equilibrium position relative to the direction of propagation of the wave such as transverse and longitudinal waves.

• Mechanical waves require a material medium through which to travel.

• The model of a wave incorporates the characteristics of amplitude, wavelength , frequency , period , wave speed , and phase.

• Electromagnetic radiation exhibits wave characteristics.

• Electromagnetic waves can propagate through a vacuum. (sound can't)

• All frequencies of electromagnetic radiation travel at the same speed in a vacuum.

• When a wave strikes a boundary between two media, reflection , transmission, and absorption occur. A transmitted wave may be refracted.

• When a wave moves from one medium into another, the wave may refract due to a change in speed. The angle of refraction (measured with respect to the normal) depends on the angle of incidence and the properties of the media (indices of refraction).

• The absolute index of refraction is inversely proportional to the speed of a wave.

• When waves of a similar nature meet, the resulting interference may be explained using the principle of superposition.

• Standing waves are a special case of interference.

• Resonance occurs when energy is transferred to a system at its natural frequency.

• Diffraction occurs when waves pass by obstacles or through openings. The wavelength of the incident wave and the size of the obstacle or opening affect how the wave spreads out.

• When a wave source and an observer are in relative motion, the observed frequency of the waves traveling between them is shifted (Doppler effect).

• States of matter and energy are restricted to discrete values (quantized).

• Charge is quantized on two levels. On the atomic level, charge is restricted to the elementary charge (charge an electron or proton). On the subnuclear level charge appears as fractional values of the elementary charge (quarks).

• On the atomic level, energy is emitted or absorbed in discrete packets called photons.

• The energy of a photon is proportional to its frequency.

• On the atomic level, energy and matter exhibit the characteristics of both waves and particles.

• Among other things, mass-energy and charge are conserved at all levels (from subnuclear to cosmic).

• The Standard Model of Particle Physics has evolved from previous attempts to explain the nature of the atom and states that:

• 1. Atomic particles are composed of subnuclear particles.

• 2. The nucleus is a conglomeration of quarks which manifest themselves as protons and neutrons.

• 3. Each elementary particle has a corresponding antiparticle.

• Behaviors and characteristics of matter, from the microscopic to the cosmic levels, are manifestations of its atomic structure. The macroscopic characteristics matter, such as electrical and optical properties, are the result of microscopic interactions.

• The total of the fundamental interactions is responsible for the appearance and behavior of the objects in the universe.

• The fundamental source of all energy in the universe is the conversion of mass into energy.