Physics Study Guide: Electric Potential, Current, Magnetism, and Electromagnetic Waves

Study Guide - Smart Notes

Tailored notes based on your materials, expanded with key definitions, examples, and context.

Dielectric: An insulating material that increases the capacitance of a capacitor by reducing the electric field within it.
Dielectric strength: The maximum electric field a dielectric material can withstand without breakdown.
Electric potential: The amount of electric potential energy per unit charge at a point in space.
Electron volt (eV): A unit of energy equal to the energy gained by an electron when accelerated through a potential difference of one volt.
Electric field lines: Imaginary lines representing the direction and strength of an electric field; they point from positive to negative charges.
Equipotential lines: Lines or surfaces where the electric potential is constant.
Potential difference: The difference in electric potential between two points; measured in volts (V).
Uniform electric field: An electric field with constant magnitude and direction.
Uniform field: A field that is the same at every point in a region.
Farad: The SI unit of capacitance.
Capacitance: The ability of a system to store electric charge per unit potential difference.
Parallel plate: A common capacitor configuration consisting of two parallel conducting plates.

Electrical potential energy: The energy stored due to the position of a charge in an electric field. Equation:
Electric energy of a charged object accelerated by a uniform electric field: Equation:
Electrical potential of a point charge: Equation:

Calculating the potential difference between two points in a uniform electric field.

Current: The rate of flow of electric charge; measured in amperes (A).
Electric current: The movement of electrons or other charge carriers through a conductor.
Conventional current: The direction positive charges would flow, opposite to electron flow.
Electron current: The actual flow of electrons, from negative to positive.
Direct current (DC): Electric current that flows in one direction only.
Alternating current (AC): Electric current that periodically reverses direction.
Ohm: The SI unit of electrical resistance.
Ohm's law: The relationship between voltage, current, and resistance. Equation:
Resistance: The opposition to the flow of electric current.
Resistivity: A material property that quantifies how strongly a material opposes current. Equation:

Current over time: The total charge passing through a point in a circuit over a specified time. Equation:
Current and voltage in a simple circuit: Using Ohm's law to find current or voltage. Equation:

Magnetic North and geographic North: Magnetic North is the direction a compass points, which differs from geographic North due to Earth's magnetic field.
B-field: The magnetic field, represented by the symbol B; measured in teslas (T).
Electromagnet: A magnet created by electric current flowing through a coil of wire.
Electromagnetism: The interaction between electric currents and magnetic fields.
Ferromagnetic material: Materials like iron, cobalt, and nickel that can be magnetized.
Magnetic field: The region around a magnet where magnetic forces can be detected.
Magnetic field lines: Lines that show the direction and strength of a magnetic field.
Right-hand rules (RHR-1, RHR-2): Rules for determining the direction of magnetic fields and forces.
Solenoid: A coil of wire that generates a magnetic field when current passes through it.

Force on a moving charge in a B-field: The magnitude and direction of the force experienced by a charge moving in a magnetic field. Equation:

Using the right-hand rule to determine the direction of force on a positive charge moving in a magnetic field.

Electric field (E-field): A field produced by electric charges; it exerts force on other charges.
Magnetic field (B-field): A field produced by moving electric charges and magnetic materials.
Electromagnetic spectrum: The range of all possible frequencies of electromagnetic radiation.
Electromagnetic energy: Energy carried by electromagnetic waves.
Electromagnetic intensity: The power per unit area carried by an electromagnetic wave.
Electromagnetic momentum: The momentum carried by electromagnetic waves.
Speed of light: The speed at which electromagnetic waves propagate in a vacuum. Equation:

Frequency and wavelength: Relationship between frequency, wavelength, and speed of light. Equation:
Energy density: The energy per unit volume in an electromagnetic field.
Ratio of maximum E-field and B-field strengths: Equation:
Electromagnetic field intensity: The strength of the electric and magnetic fields in an electromagnetic wave.