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相关概念视频

Gravimetry: Overview01:05

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Gravimetric analysis is a quantitative method where the analyte is isolated and weighed directly or after conversion into a substance of known composition. Gravimetric analysis can be classified as precipitation, electrogravimetry, volatilization, and particulate gravimetry, based on the method used to isolate the analyte.
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Consider a coffee mug hanging on a hook in a pantry. If the mug gets knocked, it oscillates back and forth like a pendulum until the oscillations die out.
A simple pendulum can be described as a point mass and a string. Meanwhile, a physical pendulum is any object whose oscillations are similar to a simple pendulum, but cannot be modeled as a point mass on a string because its mass is distributed over a larger area. The behavior of a physical pendulum can be modeled using the principles of...
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Apparent Weight01:09

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True weight is the measure of the gravitational force acting on an object. However, if the object accelerates, its measured weight is different from its true weight. Similar observations can be made when the object is submerged in water. An object's weight in water is its apparent weight, which is equal to the difference between its true weight and the buoyant forces.
Consider a person standing on a bathroom scale inside an elevator. If the scale is accurate at rest, its reading equals the...
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An object's apparent weight is its weight measured by a spring balance at its location. It is different from its true weight, the force with which the Earth pulls it, because of the Earth's rotation. Mathematically, an object's apparent weight equals its true weight minus the centripetal force that keeps it in a circular motion along with the Earth's surface every 24 hours.
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When an object is dropped, it accelerates toward the center of the Earth. If the net external force on the object is its weight, it is said to be in free fall; that is, the only force acting on the object is gravity. Galileo was instrumental in showing that, in the absence of air resistance, all objects fall with the same acceleration g. However, when objects on the Earth fall downward, they are never truly in free fall, because there is always some upward resistance force from the air acting...
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Counting is the type of measurement that is free from uncertainty, provided the number of objects being counted does not change during the process. Such measurements result in exact numbers. By counting the eggs in a carton, for instance, one can determine exactly how many eggs are there in the carton. Similarly, the numbers of defined quantities are also exact. For example, 1 foot is exactly 12 inches, 1 inch is exactly 2.54 centimeters, and 1 gram is exactly 0.001 kilograms. Quantities...
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用毫克升起的质量测量重力.

Tim M Fuchs1, Dennis G Uitenbroek1, Jaimy Plugge1

  • 1Leiden Institute of Physics, Leiden University, P.O. Box 9504, 2300 RA Leiden, Netherlands.

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概括
此摘要是机器生成的。

研究人员测量了重力.

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科学领域:

  • 量子物理学的量子物理学
  • 引力物理 引力物理

背景情况:

  • 引力是一个时空曲率,抵制量子理论统一.
  • 在微观尺度上,引力相互作用很弱,而量子效应则占主导地位.

研究的目的:

  • 为了探测量子重力效应,使用中视镜悬浮系统.
  • 在桌面尺度上测试引力系统中的量子叠加和纠.

主要方法:

  • 使用I型超导陷来 levitate一个亚毫米尺度的磁粒子.
  • 测量悬浮粒子和千克源质量之间的引力合.

主要成果:

  • 在attonewton力尺度上演示了引力合.
  • 扩展重力测量到适用于量子实验的低力状态.

结论:

  • 悬浮机械传感器对于探索量子引力至关重要.
  • 这项工作为桌面量子引力研究开辟了道路.