Joint movement occurs around an axis that is always to its plane.

perpendicular

Explanation: Joint can be found in areas of the body where two or more bones are connected together, practical examples in the human body can be traced to our elbow, wrist, hip, knee. At Each of these points mentioned, it could be observed that it serves as a meeting point for two or more bones which are linked and formed around an axis. This joints enables us to conveniently move, twist our rigid bones in different directions perpendicular to the plane (that is in a direction opposite or away from the direction of the plane).

the transfer of energy between two molecules spaced just nanometers apart plays a key role in many technologies, including photovoltaics, quantum information systems, lighting, and sensors, as well as in biophysics to measure nanometer distances and in photosynthesis. but an open question in this area is what effect, if any, the surrounding photonic environment has on this nanoscale energy transfer. by designing and performing a carefully controlled experiment to answer this question, scientists have settled the debate and found clues to improving the efficiency of many of the technologies that rely on this process.

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