Notes, summaries, assignments, exams, and problems for Physics

Capacitive Level Meters

Electric Meters radiation level 2: Capacitive meters measurement is based on the variation of capacitance, which changes when the dielectric medium between its plates varies. Capacitance is influenced by three primary factors:

• 1. Distance between electrode plates.
• 2. Size of the electrode plates.
• 3. Dielectric value of the material between the electrodes.

The capacitance change makes the oscillator operate at a level proportional to the measurement.

Vibrating Level Switches

Vibrating level switches are polled as a tuning fork vibrating via a piezo-driven 80Hz signal. If the substance covers the pitch, the signal is damped, which produces a signal that activates a relay. It is used for both liquids and solids of small particle... Continue reading "Industrial Level Measurement and Detection Systems" »

Confocal Microscopy for Thick Samples

Confocal microscopy is used for the study of thick, three-dimensional samples by producing optical sectioning without physically cutting the specimen. It utilizes high-power laser sources, which provide superior penetration depth compared to traditional methods.

How Confocal Microscopy Works

Unlike standard methods, confocal microscopy uses a pinhole diaphragm to block out-of-focus light, allowing only the light from the focal plane to pass through. This process ensures that the system detects only the fluorescence of the plane in focus, resulting in significantly higher image resolution and contrast.

Confocal vs. Epi-fluorescence

• Confocal Microscopy: High resolution and contrast achieved by blocking interference

... Continue reading "Confocal Microscopy: Principles, Advantages and Applications" »

Fundamental Concepts in Fluid Mechanics

Pressure and Phase Changes

• Evaporation: The constant movement of molecules on the surface of a liquid, allowing them to escape into the atmosphere.
• Boiling: Occurs when the pressure to which a liquid is subjected equals its vapor pressure.
• Vapor Pressure: The partial pressure exerted by molecules in the gaseous state within a container when occupying a space above a liquid.
• Saturation Pressure: The state where there is a dynamic balance between the number of molecules that evaporate and condense.
• Cavitation: A phenomenon where, if the local pressure (p) in a liquid drops to or below its vapor pressure, the liquid rapidly evaporates, forming vapor bubbles. These bubbles then move and collapse violently within

... Continue reading "Fluid Mechanics Essentials: Pressure, Viscosity, and Hydrostatic Principles" »

Earth's Gravitational Field

The gravitational field of the Earth is the disturbance that occurs in the space surrounding a body having mass. The intensity of the gravitational field at a point in space is the force with which the Earth attracts a unit mass located at that point. The weight of a body is the force with which the Earth attracts it. The gravitational potential energy of a mass m at a point in Earth's gravitational field is the work performed by the gravitational field to move the mass m from that point to infinity. The gravitational potential at a point in Earth's gravitational field is the work performed by the gravitational field to move the unit mass from that point to infinity.

• Period of revolution: Time it takes a satellite

... Continue reading "Earth's Gravitational Field and Kepler's Laws of Planetary Motion" »

Fundamental Concepts in Geodesy and Measurement

The following definitions cover essential terminology related to Earth's geometry, measurement techniques, and coordinate systems.

Magnetic Poles

Defined as the points on the surface of the Earth where the magnetic field lines are perpendicular to the surface.

Geographic Poles

Defined as the points on the Earth's surface that intersect with the planet's axis of rotation.

Bounded System (Orthogonal Cylindrical Projection)

A system of orthogonal cylindrical projection is the most appropriate for the representation of land and figures whose vertical dimensions are much smaller than their horizontal dimensions. The height of a point ($q$) is measured relative to a reference plane and can be positive (... Continue reading "Essential Definitions in Geodesy and Land Surveying" »

Center of Buoyancy

The center of buoyancy is the center of gravity of the volume of water displaced by a float for a given condition. Also known as the center of thrust, as it is, for the purpose of stability, which regards the force applied. It is represented by the letter C and in some publications with the letter B to equate the "Center of Buoyancy" of English.

Since the ship moves in waves, the position of the center of buoyancy is variable and depends on the hull shape and volume submerged at that time. The curve in the transverse plane that describes the center of buoyancy for different angles of rocking is called the curve, and its center of buoyancy ray radii.

Transverse Metacentric

Since by definition the metacenter is in the vertical... Continue reading "Understanding Ship Stability and Maritime Forces" »

Sound Perception: The Subjective Factor

Sound perception is the subjective factor that involves physiological and psychological processes occurring in the ear and brain. It allows us to classify sounds as weak, strong, pleasant, or unpleasant. This perception depends not only on the sound's intensity but also on its frequency.

Sound Reflection

Sound reflection is a phenomenon where sound waves bounce off a surface and propagate in a different direction. This principle is utilized in various applications, such as in satellite dishes to focus signals.

Echo

An echo is a distinct phenomenon caused by the reflection of sound. We can distinguish an echo from the original sound if the reflected sound arrives with a time difference of at least 0.1 seconds.... Continue reading "Understanding Sound Phenomena: Perception, Reflection, and Waves" »

Concepts and Electromagnetic Phenomena

Magnetic Field Definition

Magnetic Field: The area which shows the effects of magnetic poles is said to have a magnetic field. A magnetic field is represented by lines of force.

Magnetism: Lines of force of a magnetic field created by a permanent magnet.

Magnets

• Magnets attract or repel each other, similar to electric charges.

Magnetic Magnitudes

Magnetic Flux Density (B): The number of magnetic field lines that cross the unit area (m²).

• Magnetic Flux (Φ)
• Magnetic Field Strength (H)

Electromagnetism

Electromagnetism involves the creation of a magnetic field through an electric current, or the creation of an electrical current in the presence of a magnetic field.

Biot-Savart Law

An electrical charge (q), which moves... Continue reading "Fundamental Concepts of Magnetism and Electromagnetism" »

1. What is an Electrical Accident?

An electrical accident is a process in which a person receives electrical energy, either directly or indirectly. This can range from simple electromagnetic radiation to situations where the victim becomes electrically coupled to the network.

2. Definition of Electrical Contact

Electrical contact refers to the probability of a human body being subjected to a potential difference, resulting in an electric shock due to the passage of current through it.

3. Physiological Effects of Electrical Current Above 5A

When an electrical current exceeding 5A passes through the human body, the following physiological phenomena may occur:

• Less than one cardiac cycle: Ventricular fibrillation, early electrocution (depending on the

... Continue reading "Electrical Accidents: Understanding the Risks and Safety" »

interest of the Fourier transform
• Electronics
• Signal Theory
• Telecommunications
• Optics
• Acoustics
• Radar
• Image processing
convolution product of discrete FFT (Fast FourierTransform) => time ? N log N
-Needed a FFTper each of the two images on which you must do the convolution product. And antitransformadaa the acabarde make the product. In total, we need 3 Fast Fourier transform.
• Image Space => time NN ?
space filtering of specific frequencies freqüè preferences eliminacióde
• Periodic measurement of elements
• We will say that two vectors, orthogonal vectors are orthogonal if their inner product is zero: (u, v) = 0
• The domestic product, in this case is defined as
?Uv = 0
domestic

... Continue reading "Fourier Transform Applications and Vector Orthogonality" »