Tech Bowl 9

Decibels (dB)

The loudness of sound.

Beat

When two waves interfere constructively, producing an increase in sound level.

Beat Frequency

Equal to the difference between the frequencies of the two combining sounds.

Doppler Effect

The shift in frequency and wavelength that occurs when the source and detector are in relative motion.

Electric Charge

A quality had by protons and electrons that gives them an attractive force.

Charged

Occurs when an imbalance between the numbers of protons and electrons exists.

Coulomb's Law

Electric Field

The presence of charge creates an ___________ ___________ in the space that surrounds it.

Gravitational Field

The space surrounding the Earth a permeated by a ___________ ____________ that's created by the Earth.

Electric Dipole

When two equal but opposite charges form a pair.

Conductors

Materials that permit the flow of excess charge.

Insulators

A material whose internal electric charges do not flow freely.

Superconductor

A material that offers no resistance to the flow of charges.

Ohm's Law

Direct Current

When a current always travels in the same direction through the pathway.

Voltage

The thing that creates current.

Kirchhoff's First Law (The Junction Rule) (The Node Rule)

Says that the total current that enters a junction must equal the total current that leaves the junction.

Kirchhoff's Second Law (The Loop Rule)

Says that the sum of the potential differences (positive and negative) That traverse any closed loop in a circuit must be zero.

Net Force

The single force that could replace all the individual acting on an object and produce the same effect. Forces acting in the same direction add to together to make this.

Restoring Force

Any force that always pushed an object toward an equilibrium position.

Crietria

Goal(s) that the design success is measured against

Constriant

Limitation put on design

Design brief

A document that states the problem, what the design will do to solve it, and constraints on the design

Engineering Design Process

A systematic, iterative problem solving method

Convection

Movement of heat through a fluid

Conduction

Movement of heat through a solid

Radiation

Movement of heat through empty space by electromagnetic waves

Iterative process

a process that can be applied repeatedly with the hope of making improvement to a design

Brainstorm

To come up with as many ideas as possible without worrying about constraints.

Heat

A form of energy that is transferred by a difference in temperature.

Ablative Barrier

Removal of material from the surface of an object by vaporization, chipping, or other erosive processes.

Analyze

Interpret data to reach conclusions

Engineering

the application of practical & scientific knowledge to a methodical problem solving process.

Mechanics

the branch of physics that deals with the action of forces on bodies and with motion, comprised of kinetics, statics, and kinematics.

Speed

Also, known as velocity, it is a measure of how fast an object is moving. Change in distance over time. v=d/t

Rotational Speed

refers to how fast something is moving in a circle. It is measured in units of angular-distance per time (i.e. degree per second) or rotational cycles per time (i.e. revolutions per minute.) When someone talks about "RPM" they are referencing rotational speed (i.e. when talking about the RPM of a car engine, one is describing how fast the engine in spinning.)

Acceleration

A change in speed over a period of time is described as an acceleration; the higher the acceleration the faster the change in speed. A=v/t^2

Force

an influence that causes a change of movement, direction or shape. Force is measured in units such as Pounds or Newtons. F=M*A

Work

the exertion or effort directed to produce or accomplish something. W=F*d

Power

the rate at which work is performed and energy is converted. P= W/t

Torque

a spinning force. Torque is described by the magnitude of the force multiplied by the distance it is from the center of rotation (Force x Distance = Torque). Torque is measured in units of force*distance, such as Inch-Pounds of Newton-Meters.

Velocity

the rapidity of motion or operation; swiftness; speed.

Actuator

a servomechanism that supplies and transmits a measured amount of energy for the operation of another mechanism or system, like a gripper or launcher

DC Motor

an electric motor that runs on direct current (DC) electricity.

Voltage

electromotive force or potential difference expressed in volts.

Current

the flow of an electric charge through a material.

Stall

the unexpected or unwanted stopping of an engine or motor

Load

the weight supported by a structure or part