Waves, Fields, and Electromagnetism

  • Waves: Disturbances in Space
  • A wave is a disturbance that propagates through space, carrying energy and momentum without displacing matter.
  • Longitudinal vs. Transverse Waves
  • Longitudinal waves: Propagation direction is parallel to vibration direction. Example: Sound waves.
  • Transverse waves: Propagation direction is perpendicular to vibration direction. Example: Electromagnetic waves, S-waves (Seismic).

Similarities and Differences Between Electric and Gravitational Fields

Analogies

  • Both fields are central
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Refrigeration System Components and Installation Practices

The star of the freezer means * = -6 ºC.

Refrigeration System Components

Evaporators

  • Types: Visible or buried.
  • Temperature Conservation: Limited space and evaporator size.
  • Apparatus Combination: Network hose and multiple computers (e.g., 2 evaporators, 2 tabs).
  • Single Computer Evaporator: More coils for the freezer, less cooling capacity.
  • Circuit Perimeter: Extended around doorways to prevent frost (highest leak potential).
  • Loop: Circulates oil from the crankcase for cooling.

The vacuum is up to 30 inches.

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Structural Analysis: Design, Forces, and Stability

Link: the condition imposed on an item about to stand still or describing its trajectory. The way to realize the support links is cn.

Structure: This refers to something that is built. These consist of one or more resistance elements arranged so that both the overall structure and its components are able to remain without significant changes in geometry during loading and unloading.

Structural Design is aimed at two main objectives: 1) Meeting the requirements of functionality; 2) Safely carrying

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Understanding Electrical Current, Resistance, and Conductivity

Electrical Current

Current, or electric current, is the flow of electric charge through a material over time. This flow is due to the movement of electrons within the material. Current is measured in amperes (A), which represents coulombs per second (C/s) in the International System of Units. Electric current generates a magnetic field, a principle used in electromagnets. Current intensity is measured using a galvanometer, calibrated in amperes and called an ammeter, placed in series with the conductor.

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Thermodynamics: Heat, Work, and Energy Transfer

Heat, Work, and the First Law of Thermodynamics

Summary

The transfer of thermal energy is a form of energy transfer occurring as a result of a temperature difference. Energy inside a substance is a function of its state and usually increases with increasing temperature.

The calorie is the amount of heat required to raise the temperature of 1 g of water from 14.5 °C to 15.5 °C.

The mechanical equivalent of heat is 4186 J/cal.

The heat capacity, C, of any substance is defined as the amount of thermal

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Light Phenomena and Theories

Dispersion of Light

The index of refraction of a substance is a function of the wavelength of the incident light. It decreases with increasing wavelength. As a result, if a beam of light containing different wavelengths is incident on a refracting material, each wavelength is deviated at a different angle. This effect is called dispersion.

Interference

When two waves reach a point simultaneously, the resulting vibration at that point is the sum of the vibrations that each wave would have produced individually.

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