Symbols and Units
... be characterized by both its magnitude and direction. Scalars are any quantity in physics that can be characterized by magnitude only. ...
... be characterized by both its magnitude and direction. Scalars are any quantity in physics that can be characterized by magnitude only. ...
radiation physics
... 1. The two want to come together but there is a space (insulator) between them. 2. The opposite electric charges continue to build up. 3. Eventually the build-up is great enough that the negatively charged electrons jump to the less negative body. Eventually, continued buildup of electric charge cau ...
... 1. The two want to come together but there is a space (insulator) between them. 2. The opposite electric charges continue to build up. 3. Eventually the build-up is great enough that the negatively charged electrons jump to the less negative body. Eventually, continued buildup of electric charge cau ...
Gravitation
... - Biswas3 shows that a Lorentz covariant modification of the Newtonian potential contributes about 43 arc-secs/century. A second-rank symmetric tensor is introduced into special relativity – as a potential rather than a metric. 11. The Pioneer effect ...
... - Biswas3 shows that a Lorentz covariant modification of the Newtonian potential contributes about 43 arc-secs/century. A second-rank symmetric tensor is introduced into special relativity – as a potential rather than a metric. 11. The Pioneer effect ...
physical world
... which he proposed out of his ingenuity. Before him, there were several observations, experiments and data, on the motion of planets around the sun, motion of the moon around the earth, pendulums, bodies falling towards the earth etc. Each of these required a separate explanation, which was more or l ...
... which he proposed out of his ingenuity. Before him, there were several observations, experiments and data, on the motion of planets around the sun, motion of the moon around the earth, pendulums, bodies falling towards the earth etc. Each of these required a separate explanation, which was more or l ...
Weightlessness
Weightlessness, or an absence of 'weight', is an absence of stress and strain resulting from externally applied mechanical contact-forces, typically normal forces from floors, seats, beds, scales, and the like. Counterintuitively, a uniform gravitational field does not by itself cause stress or strain, and a body in free fall in such an environment experiences no g-force acceleration and feels weightless. This is also termed ""zero-g"" where the term is more correctly understood as meaning ""zero g-force.""When bodies are acted upon by non-gravitational forces, as in a centrifuge, a rotating space station, or within a space ship with rockets firing, a sensation of weight is produced, as the contact forces from the moving structure act to overcome the body's inertia. In such cases, a sensation of weight, in the sense of a state of stress can occur, even if the gravitational field was zero. In such cases, g-forces are felt, and bodies are not weightless.When the gravitational field is non-uniform, a body in free fall suffers tidal effects and is not stress-free. Near a black hole, such tidal effects can be very strong. In the case of the Earth, the effects are minor, especially on objects of relatively small dimension (such as the human body or a spacecraft) and the overall sensation of weightlessness in these cases is preserved. This condition is known as microgravity and it prevails in orbiting spacecraft.