Lights Flashcards
Light is form of energy which a travel as
Electromagnetic waves
The branch of physics the deal with the properties and the applications of light is called
Optics
When the object is far away (at infinity)concave mirror
Image formed at?
Principal focus
Image is real , inverted and highly diminished in size
When the object is beyond the centre of curvature concave
Image formed between the principal focus service centre of curvature
Image is real inverter and smaller than object
And the object is at the centre of curvature concave
The image is at the centre of curvature itself
Image is real inverted and same size as the object
When the object is in between the centre of curvature and principle focus
The images beyond centre of curvature
Real inverted and magnified
When the object is at the principal focus concave
No image can be captured on the screen nor any virtual image can be seen
When the object is in between the focus and the pole
The image is behind the mirror
It is virtual erect and the magnified
We follow here set of sign convention called __________ to measure distance in ray diagram
Cartesian Sign convention
Cartesian sign convention is used to measure distance in_______
Ray diagram
Mirror equation
1/f = 1/u + 1/v
f focal length
U distance of the object
v distance of the image
Linear magnification m
m= hi/ho
Hi height of the image
Ho height of the object
m= -v/u
A negative sign in the value of magnification indicates that the images ______
A positive sign in the value of magnification indicates the image is ________
Real
virtual
Uses of concave mirror
Dentist head mirror
makeup mirror
torch
headlights
searchlight
solar heater
Stellar object are at an infinite distance. Therefore, image formed by a concave mirror would be the minister and inverted
Yet aasvanical telescope uses – mirror
Concave mirror
In early 17th century the Italian scientist who tried to measure the speed of light
Galileo Galilee
In 1665 Danish astronomer who first estimated speed of light by observing one of the 12th moon of planet _______.
Ole Roemer
Jupiter
Ole roemer estimated the speed of light to be about
220000 kilometre per second
Some organisms can make their own light too this ability is called
Bioluminescence
Worms, fish, squid, starfish and some other organism that live in the dark sea habitat glow or flashlight to scare of predator
In which year first language estimate was made by Armand fizeau
1849
today the speed of light in vacuum is known to be almost exactly 3 lakh kilometre per second
The bending of light rays when the process obliquely from one medium to another medium is called
Refraction of light
This deviation in the path of light is due to the change in velocity of light in the different medium
Velocity of light depends on the nature of medium in which travel. velocity of light is more in a rare medium(low optical density) than in a denser medium (high optical density)
When ray of light travels from optical rare medium to optically denser medium it bends toward the?
When a Ray of light travel from an opticaly denser medium to an optically rare medium it Bends?
A Ray of light incident normally on a denser medium
1 Normal
2 It bends away from the normal
3 Goes without any deviation
The law of refraction of light is also know as
Snell’s law of refraction
_______ is the main cause for The spectacular brilliance of diamond and twinkling of stars
Total internal reflection
The refractive index of the material of the core is ________ than that of the cladding
Higher
Optical fibres work on the phenomenon of dash
Total internal reflection
Who is the father of fibre optics
Narender Kapany
_________is a form of energy which you produce the sensation of site
Light
Distance between the pole and the principal focus of the spherical mirror is called
Focal length
F= R/2
R radius of curvature of mirror
The angle of deviation depends on the refractive index of the glass
True
The angle of deviation of light rays in a prism depend on the angle of
Incidence
According to cartesian sign convention which mirror and which lens has negative focal length
Concave mirror and concave lens
Find the size, nature and position of the image formed when an object of size 1 cm is placed at a distance of 15 cm from a concave mirror of focal length 10 cm.
-2 cm
Height of the image is -2 cm
An object 2 cm high is placed at a distance of 16 cm from a concave mirror which produces a real image 3 cm high. Find the position of the image.
Position of image -24cm
