Physics

Dictionary - R


  • radiation: Transmission of energy through space in a straight line at a speed of up to 300,000 km / s (light, heat, radio, or free corpuscles, where no obstacles are encountered). Beam of material particles (gas, liquid or solid) in motion. Light flux emitted per surface unit.
  • radian: Angle unit; central angle that intersects an arc of circumference which, rectified, is equal to the length of the radius.
  • radio: White metallic element, bright, alkaline earth, intensely radioactive, chemically similar to barium; Ra symbol, atomic number 88, atomic mass 226.05. Telephony or cordless telephone transmitter or receiver. Radio apparatus that receives the hertzian waves, through which the sounds are transmitted at greater distances.
  • radioactive: radioactive. Relative to or owned by, or radioactive. Caused by radioactivity.
  • lightning: Line or trace of light that the stars and other luminous bodies emit. Set of rectilinear movements through which the vibrations of bodies propagate, resulting in the production of light, heat, etc. Line which, starting from the center of the circle, will end in the circumference; half diameter of a circumference. The shortest distance from the center to each of the points on the surface of a sphere or spheroid. The distance from the center to the vertices of a regular polygon. The distance from the center to each point of a sharp curve. The distance from a central point or center to the periphery in a given area.
  • rarefaction: Decreased weight and density of a body while conserving the same volume.
  • reaction: Act or effect of reacting. Action that resists or opposes the other; resistance. Reflex action or resistance that a body opposes by its inertia to another that acts on it, or to a force that requests it. A process whereby the reciprocal action between two or more substances is formed, one or another, of different characteristics. Action or movement in the opposite direction to a previous movement or action and caused by that action or movement.
  • reactive: That makes it react or causes reaction.
  • reactor: That reacts. Reactionary. Reaction driving motor in which the combustion thermal energy is transformed into expansion kinetic energy.
  • referential: Which is used as a reference. Rigid system against which the spatial and temporal coordinates of physical events may be specified; reference system.
  • reflection: Back or kick that makes the body elastic, jumping from the body to which it was hit. Direction deviation that a body suffers, when, animated by a certain speed, finds another resistant body; bounce off. Return of light or sound. A phenomenon that occurs when a ray of light or heat strikes a flat, polished surface and returns to the middle from which it came.
  • reflection: What is done through reflection; reflected.Indirect. Imitated, reproduced. Effect produced by reflected light; streetlight.
  • refraction: Deviation that the rays of light, heat or sound suffer when passing from one medium to another. Change of direction of circulation of electric or electromagnetic energy, when passing from one to another medium of different conductivity. Deviation that a moving body suffers when passing a resistant medium.
  • relative: Which is calculated by reference to a proportion, to a comparative value; proportionate.
  • Yield: Useful effect of any machine.
  • resistance: Cause that counteracts the action of a force. Cause that opposes the movement of a body. Ownership of electrical conductors to oppose the passage of electric current, consuming part of its electromotive force, which is transformed into heat. Force that opposes the movement; inertia.
  • resistor: Part that increases the electrical resistance of a circuit.
  • resonance: Effect that, in the frequency of a mechanical or electrical system, produces the intervention of external forces.
  • straight: Line establishing the shortest distance between two points; straight line.
  • normal straight: Perpendicular line. It is said of the line perpendicular to the tangent of a curve.
  • retrograde: That goes backwards, which opposes progress.
  • Reverb: Extension of a reflection sound on the walls of an enclosed room.
  • hard: Not flexible; hard. Straight, hard.
  • bearing: Rolling action or effect.
  • rotation: Circular movement of a body that rotates around an axis or about itself. Movement performed by a star around its own axis. Revolution of a surface around a line that gives rise to the formation of a solid.
  • roughness: Roughness.