PHY 102 PLUS AND PDFS

Physics: Magnetism and Electricity Magnetism: - Definition: The force exerted by a magnet on other magnets, electric currents, and moving charges. - Types: - Permanent magnets: Magnets that retain their magnetism even after the removal of the external magnetic field. - Electromagnets: Magnets produced by electric currents flowing through a coil of wire. - Properties: - Magnets have two poles: north pole and south pole. - Like poles repel each other, while unlike poles attract each other. - Magnetic field lines flow from north pole to south pole. - Examples: - Bar magnets, horseshoe magnets, electromagnets, Earth's magnetic field. - Formulas: - Magnetic force: F = qvBsinθ, where q is the charge of the moving particle, v is its velocity, B is the magnetic field strength, and θ is the angle between v and B. - Magnetic flux: Φ = BAcosθ, where B is the magnetic field strength, A is the area of the surface perpendicular to the magnetic field, and θ is the angle between B and the normal to the surface. Electricity: - Definition: The flow of electrons through a conductor. - Types: - Direct current (DC): Current that flows in one direction only. - Alternating current (AC): Current that flows back and forth in a regular pattern. - Properties: - Current is measured in amperes (A). - Voltage is measured in volts (V). - Resistance is measured in ohms (Ω). - Ohm's law: V = IR, where V is the voltage, I is the current, and R is the resistance. - Examples: - Light bulbs, electric motors, radios, televisions. - Formulas: - Ohm's law: V = IR - Power: P = VI, where P is the power, V is the voltage, and I is the current. - Electrical energy: E = Pt, where E is the energy, P is the power, and t is the time.