Module 10 Flashcards
It defines a kind of motion that shows repetition and definite pattern.
Harmonic motion
It is the branch of science dealing with the study, analysis, and application of sound.
Acoustics
It is a disturbance of molecules within a given substance.
Sound
It is a medium where sound propagates without carrying over the matter where it moves. It do not only carry sounds but also different things such as electrical signals, light, and so on.
Wave
It is a wave that results from interaction with matter.
mechanical wave
What are the three types of mechanical waves?
Surface wave, longitudinal wave, and transverse wave.
It is a wave that propagates along with the interface between different media. This mechanical wave creates a disturbance on the matter’s surface. The wave generated carries over the energy of the source of the disturbance.
surface wave
It is a wave whose vibrations travel along the direction of the wave. Thus, if a wave is moving to the right, the vibrations also move to the right. This wave creates areas of compression where loose molecules clump together during transmission at certain intervals. This wave travels fastest in a solid, which becomes nonexistent in a vacuum, where no molecules can support the wave.
longitudinal wave
It is a wave whose vibrations travel perpendicularly from the wave’s direction. It travels at certain intervals and is usually drawn like a sine curve. It travels the fastest in a vacuum, which becomes nonexistent in a solid, where the matter only absorbs the energy carried by the wave.
transverse wave
What are the parts of a transverse wave?
Crest, trough, amplitude, wavelength, and frequency
It is the highest point of the transverse wave.
Crest
It is the lowest point of the transverse wave.
Trough
It is the distance between the peak or trough of the wave and the equilibrium position.
Amplitude
It is the distance between two (2) crests or troughs. Its symbol is the Greek letter lambda (𝜆).
wavelength
It is the number of waves per measured time.
frequency
It is the densest point of the longitudinal wave.
compression
It is the loosest point of the longitudinal wave.
rarefaction
A longitudinal wave’s _______ is the distance between two (2) compressions or
rarefactions.
wavelength
It is the measure of how fast a wave propagates from the source traveling outwards.
Wave speed (𝑣)
It is a phenomenon that occurs when an object with a natural frequency receives a forced vibration at a similar frequency.
Resonance
It is any cord that is pulled taut, and its center is allowed to vibrate when plucked, strummed, or any other action that will cause it to vibrate.
string
It is a structure that allows frequencies to resonate along the length of the pipe before going out, with flutes as an example.
open-ended tube
A wave that behaves similarly to a vibrating string.
open-end air column
It is a system that limits the frequency by forcing it to move to the other end, like how we create sound by blowing from an empty coke bottle.
close-end air column
The lowest possible frequency for a standing wave is known as its _____ _____, which can be determined by the presence of nodes and antinodes.
fundamental frequency
Every wave, whether it’s from sunlight or earthquakes, carries energy.
Wave Energy
This is the rate at which energy is transferred by the wave.
Wave Power
This is the amount of power that passes through a unit area of the wave’s medium.
Wave Intensity
Occurs when two waves simultaneously interact with each other or when both waves happen at the same time.
Wave Superposition
The formation of a reflected pulse is similar to the overlap of two (2) pulses traveling in the opposite direction. These converging pulses create a superposition, where the pulses overlap and pass each other; the total displacement of the string is the algebraic sum of the displacements at that point in the individual pulses.
The Pulse Behavior
It occurs if waves are in sequence. When two waves overlap in phase, their crests combine to create a larger wave with an amplitude equal to the sum of the two waves.
Constructive Interference
It occurs if waves counter each other. When two waves overlap out of phase, their crests and troughs align, and they cancel each other out or form a smaller wave. The resultant wave no longer disturbs the medium.
Destructive interference
A wave that behaves differently. It can have superposition, but its fixed ends dictate its behavior.
Sinusoidal Behavior
It is the section in which the string never moves.
Nodes
It is the section where the string moves and where the amplitude is at its greatest.
antinode
These are waves that appear stationary. They are also capable of both constructive and destructive interferences; the only downside is that they cannot transfer energy.
Standing waves
Standing wave with a definite length L and both ends fixed, like in guitars, violins, and pianos.
Normal Mode
It is produced by the compression and expansion of the medium. It is also generated from the vibrations of an object.
Sound
It always travels outward in all directions from the source, with an amplitude that depends on the direction and distance from the source.
Sound waves
A measure of the size of the variation in air pressure caused by the sound wave.
Pressure Amplitude
It is the change in frequency of a wave caused by the movement of the source relative to the observer. As the source approaches, the frequency increases; as it moves away, the frequency decreases.
Doppler shift
It is any substance that
characterizes flow, i.e., any substance that has no rigid structure is amorphous and conforms to the shape of the receptacle it is in.
Fluid
It is defined as the amount of mass m per unit volume V of a substance. It can be computed by simply dividing the mass of the object by its volume. Its SI unit is kg/m3.
Density
A fluid’s_____ _____ is the ratio of a fluid’s density compared to a standard fluid density.
specific gravity (𝑔𝑠𝑝)
It is a measure of how much force is applied over a given area. It is the magnitude of the force on a surface per unit area. The force is perpendicular to the surface area.
Pressure (P)
It is the measure of how it resists flowing. Physically, it is the ratio of shearing stress (𝜏) to the velocity gradient in a fluid. Its unit is pascal-second (Pa ⋅ s), but it is rarely used in the scientific community, preferring the Poise (P) and the dyne-s/ cm2 over it
Viscosity
The unit Poise is named in honor
of the French physiologist _____ _____
Jean Poiseuille
Fluids exist only in two (2) states:
static and dynamic
A fluid is considered to be _____ if there is no change in a fluid contained in a receptacle. This means that the density is constant and uniform throughout its volume. This is one (1) of the characteristics of an ideal fluid.
static
A principle that states that pressure applied to a fluid in a closed container is transmitted equally to every point of the fluid and the walls of the container.
Pascal’s Principle
A principle that states that states that any object completely or partially submerged in fluid experiences an upward buoyant force equal in magnitude to the weight of the fluid displaced by the object.
Archimedes’ Principle
A fluid is considered to be ____ if there is motion involved or if there are changes in the system. The motion of real fluids is very complicated and not yet fully understood.
dynamic
The following are the four (4) assumptions about ideal fluids:
- Incompressible flow
- Laminar flow
- Newtonian flow
- Irrotational flow
The similar assumption to fluids at rest; the density is constant and uniform.
Incompressible flow
The flow of fluids is said to be steady or laminar if the velocity of moving fluid at a fixed point does not change.
Laminar flow
The viscosity of a fluid dictates the rate of flow of a fluid. If one dips their fingers in a Newtonian fluid, there is absolutely nothing to slow one down.
Newtonian flow
A British scientist who
was also 3rd Baron Rayleigh, noted that a boat moving through
a Newtonian fluid will never come to a stop even if all engines
were shut down.
John William Strutt
A type of flow where fluid particles do not rotate about their center of mass, even though they may move in curved paths.
Irrotational flow
It states that if the speed of a fluid element increases as the element travels along a horizontal streamline, the pressure of the fluid must decrease, and conversely.
Bernoulli’ Principle
_____ _____ formulated an equation that relates the pressure of a moving fluid to the fluid density, speed, and altitude.
Daniel Bernoulli
It states that the speed of a liquid flowing under the force of gravity out of an opening in a tank is proportional jointly to the square root of the opening’s vertical location. Simply put, if some liquid flows at an opening located near the base of a tank, its flow velocity is equal to the flow velocity of a liquid flowing out from the opening located at the top of the tank.
Torricelli’ Principle
He is an Italian physicist that once studied the principles of
how the flow distance of fluids decreases as the height increases while
maintaining the same flow velocity.
Evangelista Torricelli
What are the limitations of Bernoulli’s Equation?
- The velocity of a given fluid flowing in a system is maximum when near the center of the pipe it flows in, in which the velocity gradually decreases as the fluid comes near the pipe’s walls. Thus, in every equation and problem solving, the fluid’s mean velocity is used due to the inconsistency of the fluid’s velocity within the system.
- There are still external forces acting on the fluid, which affects the flow rate of the fluid. Thus, in using the Bernoulli equation, the scenario must neglect such outside forces, which should be taken into account in reality. So, if energy is transferred in the flowing system, it will be taken into consideration.
- In the case of turbulent flows, some kinetic energy is converted into heat energy. In a viscous (similar to thick) flow, some of the energy is lost due to shear forces. Therefore, all such losses must not be taken into account whenever using this equation.
- Should the fluid flows within a curved path, the energy due to centripetal motion must be considered.
What are the assumptions of Bernoulli’s Equation?
- The fluid must be ideal and incompressible, meaning it can act on any scenario.
- The flow must be steady, meaning no disruptions.
- The flow must be one-dimensional.
- The fluid velocity must be uniform over the section and must be equal to its mean velocity.
- The only forces allowed to interact with the system are gravity and pressure.
