Reflection
Physics · परावर्तन · 15 facts
Reflection: light bouncing back from surface; two laws
1st Law: angle of incidence = angle of reflection
2nd Law: incident ray, reflected ray, normal in same plane
Plane mirror: virtual, erect, same-size, laterally inverted image
Plane mirror image distance = object distance
Concave (converging): torches, headlights, shaving mirrors, solar furnaces
Convex (diverging): rear-view mirror (wider field of view)
Mirror formula: 1/v + 1/u = 1/f; Magnification m = -v/u
Concave: real inverted image (mostly); virtual when object between P and F
Convex always forms virtual, erect, diminished image
R = 2f (radius of curvature = 2 x focal length)
Periscope: two mirrors at 45 degrees to see over obstacles
Regular reflection: smooth surface; Diffuse: rough surface
Full-length mirror needs only half person height
Kaleidoscope: multiple reflections create symmetrical patterns