LIGHT
light are electromagnetic waves that propagate vertically and can be transmitted(refracted).
A. Light reflectance
Rays of light can be divided into three, namely:
1. Light beam spread (divergent)
2. Collects the light rays (convergent)
3. Parallel light rays
There are two types of reflection of light, namely:
@ Diffuse Reflection (diffuse) occurs when light rays fall on a rough surface (not flat)produces a shadow
@ Regular Reflection occurs when light rays falling on a flat surface (smooth / shiny),produces a shadow
Law of reflection of light (Snell's law):
"Light come, light reflective, and the normal line lies in one plane. Angle comes in (i) equals the reflection angle (r)".
The mirror is divided into three types, namely:
1. Flat mirrors
The properties of a flat mirror:
@ The image formed is the intersection of the extension of the reflected ray (maya).
@ Distance equal to the distance the shadow object.
@ Upright position as the original object.
@ Contrary to the side (right side of the object into the left side of the shadow)
Two flat mirrors which form the angle alpha is:
n = 360/alfa-1
n = number of shadow
alpha = the angle formed by the mirror
The benefits of a flat mirror is decorated and used for the periscope.
2. Sunken mirror
The properties of concave mirrors:
@ Can collect light rays (convergent)
@ Fingers and focus positive (+)
benefits of a concave mirror, can magnify the image as a reflection on the vehiclespotlights and lights on a microscope slide.
3. convex mirror
The properties of convex mirrors:
@ Can spread the light beam (divergent)
@ The radius and the focus of negative
@ benefits convex mirror is used as a rearview mirror on vehicles.
@ Image formed by convex mirrors are always virtual / virtual, upright, reduced and tucked behind the mirror.
B. Light refraction
Light refraction is the bending direction of propagation of light when it enters anothermedium of different optical density.
1. Law Pembiasa light
@ Rays coming from close to the tenuous medium will stay away from the normal line
@ Rays come from tenuous medium will be close to meeting the normal line
2. Perfect reflection
Conditions of total reflection occurs:
@ Rays coming from the medium into the boardroom meeting n1> n2
@ Angle of incidence angle greater than the limit
Limit angle is the angle formed when rays parallel to the boundary bias
3. Parallel Plan of refraction of the glass
@ The first refraction, when light comes into the plan parallel glass
@ Second refraction, when light comes flannel leave plan
4. Refraction in the prism
beta rays = r1 + i2
beta = angle refracting rays
5. Refraction on curved surfaces
M = s1 n2
__ X ___
n1 s0