Physics: Kinematics and Dynamics Flashcards

These vocabulary flashcards cover foundational physics concepts including measurement units, kinematics (laws of motion), and dynamics (Newton's laws, forces, and mechanical work) as presented in the lecture transcript.

Physics

A natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force.

Empirical Method

A methodology in physics based on observation, inductive reasoning, formulating a hypothesis, and testing through experiments to reach a theory.

SI-System

The International System of Units, which includes base units such as the meter for length, kilogram for mass, and second for time.

Meter ($m$)

The base unit of length in the SI-System.

Kilogram ($kg$)

The base unit of mass in the SI-System.

Second ($s$)

The base unit of time in the SI-System.

Kelvin ($K$)

The base unit of temperature in the SI-System.

Candela ($cd$)

The base unit of luminous intensity in the SI-System.

Ampere ($A$)

The base unit of electric current in the SI-System.

Prefix Factor: Kilo ($k$)

A unit prefix representing a factor of $10^{3}$.

Prefix Factor: Centi ($c$)

A unit prefix representing a factor of $10^{-2}$.

Reference System (Bezugssystem)

A coordinate system used to describe the position and motion of objects in space relative to a starting point or observer.

Kinematics

The branch of mechanics that describes the motion of objects without considering the forces that cause the motion.

Motion (Bewegung)

The change in location of an object in space as a function of time ($t$).

Average Velocity ($\bar{v}$)

The total displacement divided by the total time interval, expressed as $\bar{v} = \frac{\triangle s}{\triangle t}$.

Instantaneous Velocity ($v$)

The velocity of an object at a specific point in time, defined as the limit of the average velocity as the time interval approaches zero: $v = \text{lim}_{\triangle t \to 0} \frac{\triangle s}{\triangle t}$.

Uniform Motion (Gleichförmige Bewegung)

A type of motion where the velocity ($v$) is constant and acceleration ($a$) is zero. The position law is $x(t) = x_{0} \text{ ± } v \times t$.

Acceleration ($a$)

The rate at which velocity changes over time, measured in $m/s^{2}$.

Uniformly Accelerated Motion

Motion where acceleration is constant ($a = a_{0}$). The velocity law is $v(t) = v_{0} + a \times t$ and the position law is $x(t) = x_{0} + v_{0} \times t + \frac{1}{2} \times a \times t^{2}$.

Acceleration due to Gravity ($g$)

The constant acceleration experienced by an object in free fall, approximately $9.81 \text{\,} m/s^{2}$ toward the center of the Earth.

Free Fall (Freier Fall)

A rectilinear, uniformly accelerated motion caused solely by gravity, occurring in the absence of external influences like air resistance.

Frequency ($f$)

The number of revolutions or cycles per unit of time, measured in Hertz ($Hz$), where $f = \frac{1}{T}$.

Period ($T$)

The time required for one full revolution or cycle.

Dynamics

The branch of physics that studies the causes of motion, specifically the effects of forces acting on masses.

Force ($F$)

A vector quantity that can cause acceleration, change of direction, or deformation of a body. Its unit is the Newton ($N$).

Newton ($N$)

The SI unit of force, defined as $1 \text{\,} kg \times 1 \text{\,} m/s^{2}$.

Newton's Second Law

States that the force acting on an object is equal to the mass of that object multiplied by its acceleration: $F = m \times a$.

Weight ($F_{G}$)

The force exerted on an object due to gravity, calculated as $F_{G} = m \times g$.

g-Force

A concept comparing a force and its resulting acceleration to the standard acceleration due to gravity ($1g = 9.81 \text{\,} m/s^{2}$).

Vector

A mathematical representation of an entity that has both magnitude (strength) and direction, depicted as an arrow starting from an application point.

Forces on an Inclined Plane

The decomposition of gravity ($F_{G}$) into the Downhill force ($F_{H}$) parallel to the plane and the Normal force ($F_{N}$) perpendicular to it.

Downhill Force ($F_{H}$)

The component of the gravitational force that pulls an object down a slope, calculated as $F_{H} = F_{G} \times \text{sin}(\text{α})$.

Normal Force ($F_{N}$)

The force perpendicular to the surface of contact, calculated as $F_{N} = F_{G} \times \text{cos}(\text{α})$.

Friction force ($F_{R}$)

A force that opposes the relative motion of surfaces in contact, categorized into static, sliding, and rolling friction.

Hooke's Law (Hookesches Gesetz)

States that the spring force ($F_{f}$) is proportional to its extension or compression ($s$): $F_{f} = D \times s$, where $D$ is the spring constant.

Spring Constant ($D$)

A measure of the stiffness of a spring, expressed in $N/m$, representing how much force is needed for a specific displacement.

Newton's Third Law (Interaction Principle)

States that if body A exerts a force on body B ($F_{A \to B}$), then body B exerts an equal and opposite force on body A ($F_{B \to A} = -F_{A \to B}$).

Newton's First Law (Law of Inertia)

An object remains at rest or in uniform motion unless acted upon by an external force.

Mechanical Work ($W$)

Work is performed when a force moves or deforms a body. For a constant force in the direction of the displacement ($s$), it is defined as $W = F \times s$.

Joule ($J$)

The SI unit for work and energy, defined as $1 \text{\,} Newton \times 1 \text{\,} meter$ ($Nm$).

Lifting Work ($W_{hub}$)

Work performed to raise a mass to a height ($h$) against gravity, calculated as $W_{hub} = m \times g \times h$.

Acceleration Work ($W_{beschl}$)

The work required to change the velocity of a mass, calculated as $W_{beschl} = \frac{1}{2} \times m \times v^{2}$.