Physics: Simple Harmonic Motion, Density, Pressure & Pascal's Principle

Physics Terms and Concepts

• Physics is the study of matter, energy, forces, and their interactions.

Measurement and Unit

• Measurement is the process of determining the magnitude of a quantity.
• Accuracy is the degree of exactness of measurement compared to the true value.
• Precision is a measure of the consistency of measurements.

Scalars and Vectors

• Scalars are physical quantities with only magnitude (e.g., mass, age, speed).
• Vectors are physical quantities with both magnitude and direction (e.g., velocity, weight, displacement).
• FX and FY represent vector components along the x-axis and y-axis, respectively.

Equilibrium and Motion

• Static equilibrium is the condition of a body at rest, remaining at rest under the action of concurrent forces.
• Translational equilibrium is the condition of a body in motion with constant velocity.
• Force condition: the vector sum of all forces acting on the body must be zero.
• Torque condition: the sum of all torques acting on the body must be zero.
• Uniform motion: constant speed and zero acceleration.
• Uniform acceleration: velocity increases uniformly.

Laws of Motion

• Law of Inertia: a body at rest remains at rest, and a body in motion remains in motion with constant speed in a straight line, unless there is a net force acting upon it.
• Law of Acceleration: a net force (F) acting on a body of mass (m) results in acceleration (a) proportional to the force and inversely proportional to the mass.
• Law of Action and Reaction: for every action, there is always an equal and opposite reaction.

Friction

• Centripetal forces act toward the center of a circular path.
• Laws of Friction: the force of static friction between surfaces in contact is opposite the applied force, fs ≤ μsN, where μs is a dimensionless constant.
• Kinetic friction force, fk = μkN, where μk is generally less than μs.

Energy and Work

• Work is the product of the force in the direction of displacement and the magnitude of displacement.
• Energy is the capability to do work.
• Mechanical energy of a system is the sum of its kinetic energy and potential energy.
• Potential energy is the energy stored in a body due to its position.
• Kinetic energy is the energy possessed by an object due to its motion.
• Mass energy is the energy equivalent to its mass.
• Power is the rate at which work is done on an object.

Motion in One Dimension

• Simple Harmonic Motion is a type of vibratory motion where acceleration is proportional to displacement and directed toward the equilibrium position.

Fluids

• Density is the mass per unit volume (kg/m³).
• Specific Gravity (SPGR) is the ratio of a substance's density to that of water at 4°C (1.0 × 10³ kg/m³).
• Pressure is the ratio of force to area (Pa = N/m²).
• Pascal's Principle: pressure applied to an enclosed fluid is transmitted undiminished to every point in the fluid.
• Archimedes' Principle: the behavior of an object submerged in a fluid is governed by this principle.
• Buoyant force is an upward force experienced by an object partially or fully submerged in a fluid.

Thermal Properties

• Temperature is a physical property that quantitatively expresses hot and cold.
• Thermal Expansion: bodies expand as their temperature increases.
• Heat is energy transferred from one place to another due to temperature differences.
• Heat Energy is an energy transfer that takes place as a consequence of temperature differences.
• Internal Energy is the energy a substance has at some temperature.
• Calorie is the amount of heat necessary to raise the temperature of 1g of water from 14.5 to 15.5°C.
• Specific Heat is the heat capacity per unit mass.
• Molar Heat Capacity is the heat capacity per mole.
• Calorimetry is a technique for measuring the specific heat of a solid or liquid.

Waves

• Mechanical Waves require a material medium to travel (e.g., air, water).
• Transverse Waves cause the medium to move perpendicular to the direction of the wave.
• Longitudinal Waves cause the medium to move parallel to the direction of the wave.
• Surface Waves are a combination of transverse and longitudinal waves.
• Electromagnetic Waves do not require a medium to travel (e.g., light, radio).
• Matter Waves are produced by electrons and particles.

Measuring Waves

• Period is the shortest time for a point to return to its initial position (one vibration).
• Frequency is the number of vibrations per second, measured in Hz.
• Wavelength is the shortest distance between peaks or troughs.
• Velocity is the frequency multiplied by the wavelength.
• Amplitude is the distance from the equilibrium position to the crest or trough.

Electricity

• Electrostatics is electricity at rest.
• Capacitor is a device that stores electrical energy temporarily.
• Electricity is the flow of electrons from one point to another along transmission lines.
• Ohm's Law relates voltage, current, and resistance.
• Kirchoff's Laws describe the relationships between voltage and currents in circuits.

Node and Circuit

• Node is a junction in a circuit where two or more branches are joined.
• Kirchoff's Current Law: the algebraic sum of currents at a node is zero.
• Kirchoff's Voltage Law: the total voltage around a closed loop is equal to the sum of all voltage drops within the loop.