Physics of Everyday Life - Kinematics, Dynamics, and Rotational Motion (Physics Review 1)

100 vocabulary flashcards covering key terms, definitions, formulas, and units from Chapters 1 and 2 of Louis A. Bloomfield's 'How Things Work: The Physics of Everyday Life'.

Rotational Motion

Motion around a fixed point that prevents translation.

Angular Position

An object's orientation defined by an angle relative to a fixed reference line.

Angular Displacement

The angle through which an object rotates during a given time interval.

Radian

The standard unit of angle generally used in rotational motion calculations.

Polar Coordinate System

A coordinate system used to analyze circular motion relative to a fixed origin point $O$ and a reference line.

Angular Speed

The ratio of angular displacement to the time interval, represented by the Greek letter $\nu$ or $\text{ω}$.

Angular Velocity

A vector quantity consisting of angular speed combined with the direction of rotation.

Right-Hand Rule

The rule used to determine the vector direction of angular velocity and angular acceleration.

Angular Acceleration

The ratio of the change in angular velocity to the time interval, represented by the symbol $\text{α}$ and measured in $\text{rad/s}^2$.

Torque

The rotational effect produced by the combination of a force and its point of application, represented by the Greek letter $\text{τ}$.

Lever Arm

The distance $L$ from the axis of rotation to the point where a force is applied.

Line of Action

The direction along which a force acts; if it passes through the axis of rotation, no torque is produced.

Rotational Mass (Moment of Inertia)

A measure of an object's resistance to changes in its rotation, symbolized by $I$, depending on its mass and mass distribution relative to the axis.

Newton's Second Law of Rotational Motion

The law stating that torque equals rotational mass times angular acceleration ($\text{τ} = I \times \text{α}$).

Torque Wrench

A specialized wrench that applies a calibrated torque to a bolt to prevent over-tightening and breakage.

Rotational Equilibrium

The state in which an object experiences a net torque of zero ($\text{net torque} = 0$), preventing rotational acceleration.

Newton's Third Law of Rotational Motion

The law stating that when object A exerts a torque on object B, object B exerts an equal but opposite torque on object A.

Mechanical Equilibrium

The state achieved when an object satisfies two conditions simultaneously: $\text{net force} = 0$ and $\text{net torque} = 0$.

Stability

An object's property of settling back to an upright position after being tipped slightly.

Center of Gravity (CG)

The average position of weight distribution in an object, usually located at its physical center.

Center of Mass

The average position of all the mass that makes up an object, representing its balancing point.

Newton's First Law of Rotational Motion

The law stating that an object rotating about an axis tends to remain rotating at the same speed unless acted upon by external torque.

Friction

A microscopic-level force acting between contacting surfaces that always opposes motion.

Static Friction

The friction force acting between stationary surfaces that opposes the initiation of relative motion.

Maximum Static Friction Force

The maximum force value static friction can reach before an object begins sliding.

Kinetic Friction

The friction force experienced between surfaces in relative motion, which is smaller than maximum static friction.

Rotational Kinetic Energy

The energy an object possesses due to its circular motion, calculated as $K = \frac{1}{2} \times I \times \text{ω}^2$.

Translational Kinetic Energy

The energy an object possesses due to its linear motion through space, calculated as $K = \frac{1}{2} \times m \times v^2$.

Linear Momentum

A vector quantity defined as the product of mass and velocity ($p = m \times v$), measured in $\text{kg}\text{⋅}\text{m/s}$.

Law of Conservation of Linear Momentum

The principle stating that the total momentum of a system before an interaction equals the total momentum after the interaction.

Elastic Collision

A collision in which two objects bounce off each other with no loss of energy.

Inelastic Collision

A collision in which objects bounce off each other with some loss of energy.

Completely Inelastic Collision

A collision in which colliding objects stick together after impact, resulting in the maximum possible energy loss.

Impulse

The product of an applied force and the time interval over which it acts ($\text{impulse} = F \times t$).

Recoil

The backward motion acquired by a launching system (like a cannon) when firing a projectile forward.

Angular Momentum

A measure of an object's amount of rotation, equal to rotational mass times angular velocity ($L = I \times \text{ω}$).

Law of Conservation of Angular Momentum

The principle stating that the total rotational momentum of an isolated system remains constant when no external torques act.

Angular Impulse

The product of an applied torque and the time interval over which it acts ($\text{angular impulse} = \text{χ} \times t$).

Measurement

The fundamental quantitative comparison process used as the basis for testing scientific theories.

Système International (SI)

The international standard system of units agreed upon in $1960$, based on mks units.

MKS System

A system of measurement named after its fundamental units: meter ($\text{m}$), kilogram ($\text{kg}$), and second ($\text{s}$).

Gaussian System (cgs)

A measurement system named after its fundamental units: centimeter, gram, and second.

US Customary System

An everyday measurement system (imperial) utilizing units like feet ($\text{ft}$) and pounds ($\text{lb}$).

Scalar Quantity

A physical quantity that specifies magnitude only, such as speed or temperature.

Vector Quantity

A physical quantity that specifies both magnitude and direction, such as velocity or force.

Position

The location of an object described relative to a chosen origin or reference point.

Reference Point (Origin)

A fixed point used as a baseline to define the relative position of an object.

Distance

A scalar measure of the actual path followed by an object from point A to point B.

Displacement

A vector quantity representing the shortest straight distance and direction from point A to point B.

Speed

A scalar measure of how fast an object is moving, calculated as distance divided by time.

Velocity

A vector quantity containing both speed magnitude and direction of motion ($v = \frac{d}{t}$).

Average Human Walking Speed

The standard baseline walking speed given as $5\text{ km/h}$.

Acceleration

The rate at which velocity changes over time, occurring when speed, direction, or both change.

Average Acceleration Formula

The formula defined as change in velocity divided by the time interval ($a = \frac{v_f - v_i}{t_f - t_i}$).

Deceleration

Acceleration that is opposite in direction to velocity, causing an object to slow down.

Inertia

The inherent property of all objects to resist changes in their velocity.

Mass

A quantitative measure of the inertia or sluggishness of a body, measured in kilograms ($\text{kg}$).

Newton's First Law of Motion

The law stating that a body at rest stays at rest, and a body in motion stays in motion in a straight path, unless acted upon by an external force.

Newton's Second Law of Motion

The law stating that acceleration is directly proportional to net force and inversely proportional to mass ($a = \frac{F_{\text{net}}}{m}$).

Net Force

The vector sum of all individual forces acting simultaneously on an object.

Newton's Third Law of Motion

The law stating that whenever one object exerts a force on a second object, the second object exerts an equal and opposite force on the first.

Action-Reaction Pair

The pair of simultaneous, equal, and oppositely directed forces exerted on two interacting objects.

Weight

The amount of gravitational pull on an object, equal to mass times acceleration due to gravity ($w = m \times g$).

Acceleration Due to Gravity ($g$)

The rate at which the downward speed of a falling object increases each second.

Precise Value of Acceleration Due to Gravity

The precise physical constant specified as $9.80665\text{ m/s}^2$.

Standard Course Value of $g$

The approximate gravitational acceleration used for calculations in this course, specified as $g \text{ ≈ } 10\text{ m/s}^2$.

Newton (Unit)

The SI unit of force, where $1\text{ N}$ is equal to approximately $0.225\text{ lb}$.

Lunar Gravitational Acceleration ($g_{\text{moon}}$)

The acceleration due to gravity on the Moon, equal to approximately $1.6\text{ m/s}^2$ (about $\frac{1}{6}$ of Earth's gravity).

Jovian Gravitational Acceleration ($g_{\text{jupiter}}$)

The acceleration due to gravity on Jupiter, equal to approximately $23\text{ m/s}^2$ (about $2.3$ times Earth's gravity).

Final Velocity Formula for Constant Acceleration

The kinematic equation given by $v_f = v_i + a \times t$.

Free Fall

The state of motion where gravity is the only force acting on a falling object, with negligible air resistance.

Free Fall Distance Formula

Galileo's equation for the distance an object falls from rest: $y = \frac{1}{2} \times g \times t^2$.

Projectile Motion

Two-dimensional motion of an object launched into space that moves under the sole influence of gravity.

Projectile

An object thrown, hit, kicked, or shot that travels freely under the influence of gravity.

Non-Projectiles

Objects such as rockets or jet planes that drive themselves using internal power rather than moving solely under gravity.

Angle for Maximum Projectile Range

The elevation angle required to achieve maximum horizontal range for a projectile, specified as $45^\text{°}$.

Vertical Velocity at Projectile Peak

The vertical component of a projectile's velocity when it reaches the highest point of its path, equal to $0\text{ m/s}$.

Orbital Motion

The trajectory achieved when an object is thrown horizontally with a sufficiently high velocity so that it falls continuously around the Earth.

Support Force (Normal Force)

The upward force exerted by a surface to support an object against gravity.

Work

The product of the applied force and the distance an object moves in the direction of the force ($\text{Work} = F \times d$).

Joule

The SI unit for work and energy, equivalent to one Newton-meter ($1\text{ N}\text{⋅}\text{m}$).

Power

The rate at which work gets done per unit time interval ($\text{Power} = \frac{\text{Work}}{\text{time}}$).

Watt

The SI unit of power, equivalent to one Joule per second ($1\text{ J/s}$).

Energy

The physical capacity or ability to do work, measured in Joules ($\text{J}$).

Kinetic Energy Formula

The mathematical formula for linear motion energy: $\text{KE} = \frac{1}{2} \times m \times v^2$.

Gravitational Potential Energy (GPE)

The energy an object possesses due to its elevated position above the Earth.

Gravitational Potential Energy Formula

The formula used to calculate potential energy: $\text{GPE} = m \times g \times h$.

Law of Conservation of Energy

The principle stating that total energy remains constant, transforming between potential and kinetic forms ($\text{KE} + \text{PE} = \text{constant}$).

Torque Formula (Force and Distance)

The geometric formula calculating torque as force times lever arm distance ($\text{τ} = F \times L$).

Torque Formula (Rotational Mass)

The rotational dynamics formula calculating torque as rotational mass times angular acceleration ($\text{τ} = I \times \text{α}$).

Clockwise Rotation Convention

The polar coordinate directional convention in which clockwise angles and angular velocities are defined as negative.

Counter-Clockwise Rotation Convention

The polar coordinate directional convention in which counter-clockwise angles and angular velocities are defined as positive.

Unit of Angular Speed

The SI measurement unit defined as radians per second ($\text{rad/s}$).

Unit of Angular Acceleration

The SI measurement unit defined as radians per second squared ($\text{rad/s}^2$).

Unit of Torque

The SI measurement unit defined as Newton-meters ($\text{N}\text{⋅}\text{m}$).

Unit of Rotational Mass

The SI measurement unit defined as kilogram meters squared ($\text{kg}\text{⋅}\text{m}^2$).

Unit of Linear Momentum

The SI measurement unit defined as kilogram meters per second ($\text{kg}\text{⋅}\text{m/s}$).

Impulse Formula

The mathematical expression defined as force multiplied by time interval ($\text{impulse} = F \times t$).

Angular Impulse Formula

The mathematical expression defined as torque multiplied by time interval ($\text{angular impulse} = \text{χ} \times t$).

Recoil Velocity Formula

The formula calculating the recoil velocity of a launcher of mass $M$ firing a projectile of mass $m$ at speed $v$: $V = -\frac{m \times v}{M}$.