pneumatic trough

(noun)

device used to collect a gas over water; the height of water displaced in the tube can be used to determine the total pressure inside the tube

Related Terms

Examples of pneumatic trough in the following topics:

  • Collecting Gases Over Water

    • This arrangement is called a pneumatic trough, and it was widely used in the early days of chemistry.
    • O2 gas is collected in a pneumatic trough with a volume of 0.155 L until the height of the water inside the trough is equal to the height of the water outside the trough.
    • How many moles of oxygen are present in the trough?
    • Oxygen gas generated in an experiment is collected at 25°C in a bottle inverted in a trough of water.
    • When the water level in the originally full bottle has fallen to the level in the trough, the volume of collected gas is 1750 ml.

  • Characteristics of Birds

    • Several modifications are found in birds to reduce body weight, including pneumatization of bones.
    • Pneumatic bones are hollow rather than filled with tissue .
    • Pneumatic bones are not found in all birds; they are more extensive in large birds than in small birds.
    • Not all bones of the skeleton are pneumatic, although the skulls of almost all birds are.
    • The air sacs that extend into bones, making them pneumatic, also join with the lungs and function in respiration.

  • The Business Cycle: Definition and Phases

    • Business cycles are identified as having four distinct phases: expansion, peak, contraction, and trough.
    • The slowing ceases at the trough and at this point the economy has hit a bottom from which the next phase of expansion and contraction will emerge.
    • In the United States, it is generally accepted that the National Bureau of Economic Research (NBER) is the final arbiter of the dates of the peaks and troughs of the business cycle.
    • An expansion is the period from a trough to a peak, and a recession as the period from a peak to a trough.
    • The phases of a business cycle follow a wave-like pattern over time with regard to GDP, with expansion leading to a peak and then followed by contraction leading to a trough.

  • The Speed of a Wave on a String

    • Transverse waves have what are called peaks and troughs.
    • The peak is the crest, or top point of the wave and the trough is the valley or bottom point of the wave.
    • Refer to Figure 2 for a visual representation of these terms.The amplitude is the maximum displacement of a particle from its equilibrium position.Wavelength, usually denoted with a lambda (λ) and measured in meters, is the distance from either one peak to the next peak, or one trough to the next trough.Period, usually denoted as T and measured in seconds, is the time it takes for two successive peaks, or one wavelength, to pass through a fixed point.Frequency, f, is the number of wavelengths that pass through a given point in 1 second.
    • Peaks are the top most points of the waves and troughs are the bottom, or valleys of the waves.

  • Introduction to Light Energy

    • Scientists can determine the amount of energy of a wave by measuring its wavelength, the distance between consecutive points of a wave, such as from crest to crest or from trough to trough .
    • The wavelength of a single wave is the distance between two consecutive points of similar position (two crests or two troughs) along the wave.

  • Reflections

    • Transverse waves have what are called peaks and troughs.
    • The peak is the crest, or top point of the wave and the trough is the valley or bottom point of the wave.
    • Wavelength, usually denoted with a lambda (λ) and measured in meters, is the distance from either one peak to the next peak, or one trough to the next trough.
    • This swaps the peaks with the troughs and the troughs with the peaks.

  • Paranasal Sinuses

    • Paranasal sinuses form developmentally through excavation of bone by air-filled sacs (pneumatic diverticula) from the nasal cavity.

  • Conditions for Wave Interference: Reflection due to Phase Change

    • Destructive interference occurs when the crest of one wave meets a trough of another wave.
    • When light is reflected off a medium with a higher index of refraction, crests get reflected as troughs and troughs get reflected as crests.

  • Wavelength, Freqency in Relation to Speed

    • The amplitude is half of the distance measured from crest to trough.
    • We also observe the wavelength, which is the spatial period of the wave (e.g. from crest to crest or trough to trough).

  • Sculpture in Mesopotamia

    • Scholars believe that the gypsum Uruk trough was used as part of an offering to Inanna, the goddess of fertility, love, war, and wisdom.
    • In addition to reliefs of animals, reliefs of reed bundles, sacred objects associated with Inanna, adorn the exterior of the trough.
    • For these reasons, scholars do not believe the trough was used for agricultural purposes.
    • The trough, cylinder seals, and various other sculptures of the Uruk period serve as examples of the rich narrative imagery that arose during this time.
    • An uruk trough (3300-3000 BCE) on display at the British Museum.