Physics

Items

• rays

  A beam of radiant energy (such as light) of small cross section
• reactance

  The part of the impedance of an alternating-current circuit that is due to capacitance or inductance or both and that is expressed in ohms
• reaction

  Chemical transformation or change : the interaction of chemical entities; A process involving change in atomic nuclei
• real

  Existing as a physical entity and having properties that deviate from an ideal, law, or standard
• real number

  All numbers that can be plotted on a number line, including both rational and irrational numbers.
• reciprocal

  Inversely related
• rectangle

  A parallelogram all of whose angles are right angles
• reduce

  To diminish in size, amount, extent, or number
• reference

  Something (such as a sign or indication) that refers a reader or consulter to another source of information (such as a book or passage)
• reflection

  The production of an image by or as if by a mirror
• refraction

  Deflection from a straight path undergone by a light ray or energy wave in passing obliquely from one medium (such as air) into another (such as glass) in which its velocity is different
• relative

  A thing having a relation to or connection with or necessary dependence on another thing.
• repulsion

  The action of repelling : the force with which bodies, particles, or like forces repel one another
• resistor

  A device that has electrical resistance and that is used in an electric circuit for protection, operation, or current control
• resolve

  To split up into two or more components especially in assigned directions
• resonate

  To produce or exhibit resonance
• resultant

  Derived from or resulting from something else
• reversible

  Capable of going through a series of actions (such as changes) either backward or forward
• rigid

  Deficient in or devoid of flexibility
• rocket

  A jet engine that operates on the same principle as the firework rocket, consists essentially of a combustion chamber and an exhaust nozzle, carries either liquid or solid propellants which provide the fuel and oxygen needed for combustion and thus make the engine independent of the oxygen of the air, and is used especially for the propulsion of a missile (such as a bomb or shell) or a vehicle (such as an airplane)
• rod

  A slender bar (as of wood or metal)
• root

  A number that reduces an equation to an identity when it is substituted for one variable
• rotational

  The action or process of rotating on or as if on an axis or center
• satellite

  A celestial body orbiting another of larger size
• scalar

  A quantity (such as mass or time) that has a magnitude describable by a real number and no direction