Lecture 36 Fermats Principle Reflection and refraction Fermats
- Slides: 18
Lecture 36 Fermat’s Principle Reflection and refraction • Fermat’s Principle • Spherical mirrors • Thin lenses • Magnification
Light as wave and particles • Light is a wave, as discovered by Young et al • It has interference • It has diffraction • We will discuss these properties in late part • However, we also know that light travels on a straight-line, just like particles. • According to Newton, light is a beam of particles • Particle-wave duality: light is particle and but also wave 2
Reflection and refraction 3
Laws of reflection and refraction • 4
Propagation of Light, Fermat’s Principle (1657) • 5
Fermat's principle leads to Snell's law To find the path of least time, set dt/dx=0. Since ni = c/vi and nt = c/vt. Snell’s Law of Refraction
Constructing the image from a plane mirror • Following the light rays to form an image of an object.
The focal point and focal length of a spherical mirror • The focal point is at half of the mirror’s radius of curvature. • All incoming rays will converge at the focal point.
Thin mirrors • A O B 9
Convex spherical mirror
A system of rays may be constructed to reveal the image • Rays are drawn with regard to the object, the optical axis, the focal point, and the center of curvature to locate the image.
Refraction within a sphere • 12
Thin lenses
Thin lenses
Converging lenses •
Magnifying glass • optical axis F
Diverging lens 17
The camera • A clever arrangement of optics with a method to record the inverted image on its focal plane (sometimes film, sometimes an electronic array, it depends on your camera).
- Fermat's little theorem example
- Rainbow total internal reflection
- Refraction of sound
- Poen reaction
- Partial reflection and refraction examples
- Reflection refraction absorption transmission
- Bill nye light energy
- Invictus poem reflection
- Why can we represent light rays using a ruler
- Bill nye light optics worksheet
- Venn diagram of geometric optics and physical optics
- Klews chart
- Lighthe
- Learning task 1 reflection and refraction
- Reflection vs refraction
- Reflection refraction diffraction interference
- Cmedium
- When a wave strikes an object and bounces off
- Reflection refraction