6. 6341110295910phosphorescence: light that is emitted due to exposure of the source to UV light, and that continues to be emitted for some time in the absence of UV light.
11. Light is the only form of energy that can travel like a wave through empty space and through some materials. Light behaves like a special kind of wave, called an electromagnetic wave.
13. Electromagnetic waves are invisible and travel through a vacuum. They travel through a vacuum, such as space, at the speed of light (3.00 x 108 m/s).
25. it has the same distance as the object10.3 Images in Concave Mirrors<br />concave mirror: a mirror whose reflected surface curves inward.<br />principal axis: on a concave mirror, the line that passes through the centre of curvature,C, of the mirror and is normal to the centre of the mirror.<br />focal point: the point on the principal axis through which reflected rays pass when the incident rays are parallel to and near the principal axis.<br />focal length: the distance between the vertex of a mirror and the focal point.<br />An Object between the Focal Point and the Mirror<br />116903576835<br />1169035262890An Object between the Focal Point and the Centre of Curvature<br />1216660262890An Object beyond the Centre of Curvature<br />spherical aberration: irregularities in an image in a curved mirror that result when reflected rays from the outer parts of the mirror do not go through the focal point.<br />10.4 Images in Convex Mirrors<br />1216660257810convex mirror: a mirror whose reflecting surface curves outward.<br />Chapter 11 Refraction<br />
![Optics Unit Summary<br />Chapter 10 Light and Reflection<br />10.1 Sources and Nature of Light<br />Sources of Light<br />639381573025white light: light from hot objects is made up of many different colours mixed together. <br />incandescence: light emitted from a material because of the high temperature of the material.<br />6188710141605<br />How does an incandescent light bulb work?<br />An incandescent light bulb has a tiny tungsten wire that gets very hot and glows brightly when electric current runs through it. <br />6345555166370electric discharge: the process of emitting light by heating a gas, or vapour, instead of a wire with an electric current.<br />607506689175<br />fluorescence: light that is emitted during exposure of the source to UV (ultra violet) light.<br />There are two types of light: <br />,[object Object]](https://image.slidesharecdn.com/opticsunitsummary-100721092248-phpapp01/85/Optics-unit-summary-1-320.jpg)
![non-luminous: objects that do not emit light (flashlight that is switched off)luminescence: the emission of light by a material or an object that has not been heated. <br />Types of luminescence<br />,[object Object]](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)