Physics: Base and Derived Quantities

Fundamental physical quantities defined independently and not derived from other quantities.

Physical quantities defined using mathematical relationships from base quantities.

Length, mass, time, electric current, thermodynamic temperature, amount of substance, luminous intensity.

Speed, force, pressure, energy.

Units of measurement for base and derived quantities, part of the International System of Units.

Distance over time.

Mass times acceleration

Form the foundation for all other physical quantities.

Length of a vector, representing a value and its direction.

A vector that shows a point's location from the origin.

Vectors with the same magnitude and direction.

Perpendicular vectors.

Vectors with the same or opposite direction.

Shortest vector between two points.

Same magnitude, opposite direction.

Vectors along the same line.

Using SI units ensures worldwide consistency, simplifying international trade and collaboration.

SI units are based on precise, reproducible physical constants, ensuring consistent and accurate measurements.

SI units provide a unified framework for various scientific disciplines, making data sharing easier.

SI units are based on the decimal system, making conversions between units easy.

Standardized measurements are essential for manufacturing, quality control, and innovation in technology.

Many countries mandate SI units for legal documents and trade, ensuring fairness and consistency.

Teaching SI units globally creates a common foundation for understanding scientific principles.

A thermometer that uses mercury's expansion to measure temperature. It's known for its precision and accuracy, especially at higher temperatures.

A thermometer that uses alcohol's expansion to measure temperature. It's preferred for measuring extremely low temperatures.

A temperature scale where water freezes at 0°C and boils at 100°C. It's commonly used worldwide.

A temperature scale where water freezes at 32°F and boils at 212°F. It's primarily used in the United States.

An absolute temperature scale where 0 K represents absolute zero, the point where molecular motion stops. It's used in scientific calculations.

To convert Celsius to Kelvin, add 273.15 to the Celsius temperature. (K = °C + 273.15)

To convert Kelvin to Celsius, subtract 273.15 from the Kelvin temperature. (°C = K - 273.15)

The theoretical lowest possible temperature, where all molecular motion ceases. It's represented as 0 K on the Kelvin scale.

Heat transfer through electromagnetic waves, requiring no medium.

Radiation doesn't need a medium; it can travel through a vacuum.

Infrared radiation emitted from a hot object travels as electromagnetic waves.

The point where an object's entire weight acts as if concentrated, regardless of its orientation.

Break the object into parts, assign coordinates and weights, then use formulas for each axis.

xCoG = (∑(Wi * xi)) / ∑Wi, where Wi is weight and xi is x-coordinate of each part.

The CoG's position affects an object's stability; lower CoG means more stability.

A lower CoG makes an object more stable because it has a larger base of support.

A temperature scale widely used globally and in scientific contexts, where water freezes at 0°C and boils at 100°C.

The absolute temperature scale where 0 K represents absolute zero, the lowest possible temperature. Water freezes at 273.15 K and boils at 373.15 K.

A temperature scale primarily used in the United States, where water freezes at 32°F and boils at 212°F.

A force that arises when two objects are physically touching each other and exert a direct influence on each other.

A force that acts upon objects without the need for direct physical contact, often through fields or interactions at a distance.

Friction is a contact force that resists motion between two surfaces in contact. Think of the force you feel when rubbing your hands together.

Gravity is a non-contact force that pulls objects towards each other with a strength dependent on their masses and distance. It keeps you grounded on Earth.

A contact force that acts along a rope, string, or cable when it is pulled taut, transmitting force from one end to the other.

Heat is the energy transferred due to a temperature difference, while temperature measures the average kinetic energy of particles.

Heat always flows from a hotter object to a cooler one.

Heat is measured using a calorimeter, a device that measures the heat absorbed or released.

Temperature is measured using a thermometer, which measures the average kinetic energy of particles.

Safer, less toxic, more sensitive to temperature changes.

Accurate, good for high temperatures, expands consistently.

A quantity represented by a single number with units, describing only its magnitude, without direction.

A quantity that has both magnitude (size) and direction.

Distance is a scalar quantity, the total path length traveled. Displacement is a vector quantity, the shortest distance between start and end points, considering direction.

Speed is a scalar quantity describing how fast something moves. Velocity is a vector quantity describing both speed and direction.

Force is a vector quantity, having both magnitude (how strong) and direction (which way it pushes or pulls).

Combining vectors by considering both magnitude and direction, often visualized with arrows.

Scalars are simple, just a number with units. Vectors are more complex, requiring both magnitude and direction for a full description.

Navigation uses both scalar and vector quantities: Speed (scalar) and direction (vector) are crucial for determining a path or location.

To convert Celsius to Kelvin, add 273.15 to the Celsius temperature. (K = °C + 273.15)

To convert Kelvin to Celsius, subtract 273.15 from the Kelvin temperature. (°C = K - 273.15)

Examples of Contact Forces include: Friction, Tension, Normal Force, and Applied Force.

Examples of non-contact forces include gravity, electrostatic force, and magnetic force.

Heat transfer through direct contact between molecules, mainly in solids.

Heat transfer through the bulk movement of fluids (liquids or gases) due to temperature and density differences.

Heat transfer through electromagnetic waves, requiring no medium.

Radiation does not require a medium to transfer heat. It can travel through a vacuum.

Radiation transfers heat through electromagnetic waves. It emits infrared radiation, which can travel through space.

For irregular shapes, break the object into smaller parts, assign coordinates and weights, then use formulas for each axis to find the CoG.

Heat transfer through direct contact between molecules, happening in solids, liquids, and gases.

Heat transfer through fluid movement, like air or water. Warmer fluids rise, cooler fluids sink.

Radiation uses electromagnetic waves and doesn't need a medium, while convection relies on fluid movement.