Lights

Question 1

Light is form of energy which a travel as

Answer 1

Electromagnetic waves

Question 2

The branch of physics the deal with the properties and the applications of light is called

Answer 2

Optics

Question 3

When the object is far away (at infinity)concave mirror
Image formed at?

Answer 3

Principal focus
Image is real , inverted and highly diminished in size

Question 4

When the object is beyond the centre of curvature concave

Answer 4

Image formed between the principal focus service centre of curvature

Image is real inverter and smaller than object

Question 5

And the object is at the centre of curvature concave

Answer 5

The image is at the centre of curvature itself
Image is real inverted and same size as the object

Question 6

When the object is in between the centre of curvature and principle focus

Answer 6

The images beyond centre of curvature
Real inverted and magnified

Question 7

When the object is at the principal focus concave

Answer 7

No image can be captured on the screen nor any virtual image can be seen

Question 8

When the object is in between the focus and the pole

Answer 8

The image is behind the mirror
It is virtual erect and the magnified

Question 9

We follow here set of sign convention called __________ to measure distance in ray diagram

Answer 9

Cartesian Sign convention

Question 10

Cartesian sign convention is used to measure distance in_______

Answer 10

Ray diagram

Question 11

Mirror equation

Answer 11

1/f = 1/u + 1/v
f focal length
U distance of the object
v distance of the image

Question 12

Linear magnification m

Answer 12

m= hi/ho
Hi height of the image
Ho height of the object

m= -v/u

Question 13

A negative sign in the value of magnification indicates that the images ______
A positive sign in the value of magnification indicates the image is ________

Answer 13

Real

virtual

Question 14

Uses of concave mirror

Answer 14

Dentist head mirror
makeup mirror
torch
headlights
searchlight
solar heater

Question 15

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

Answer 15

Concave mirror

Question 16

In early 17th century the Italian scientist who tried to measure the speed of light

Answer 16

Galileo Galilee

Question 17

In 1665 Danish astronomer who first estimated speed of light by observing one of the 12th moon of planet _______.

Answer 17

Ole Roemer
Jupiter

Question 18

Ole roemer estimated the speed of light to be about

Answer 18

220000 kilometre per second

Question 19

Some organisms can make their own light too this ability is called

Answer 19

Bioluminescence
Worms, fish, squid, starfish and some other organism that live in the dark sea habitat glow or flashlight to scare of predator

Question 20

In which year first language estimate was made by Armand fizeau

Answer 20

1849
today the speed of light in vacuum is known to be almost exactly 3 lakh kilometre per second

Question 21

The bending of light rays when the process obliquely from one medium to another medium is called

Answer 21

Refraction of light

Question 22

This deviation in the path of light is due to the change in velocity of light in the different medium

Answer 22

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)

Question 23

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

Answer 23

1 Normal
2 It bends away from the normal
3 Goes without any deviation

Question 24

The law of refraction of light is also know as

Answer 24

Snell’s law of refraction

Question 25

_______ is the main cause for The spectacular brilliance of diamond and twinkling of stars

Answer 25

Total internal reflection

Question 26

The refractive index of the material of the core is ________ than that of the cladding

Answer 26

Higher

Question 27

Optical fibres work on the phenomenon of dash

Answer 27

Total internal reflection

Question 28

Who is the father of fibre optics

Answer 28

Narender Kapany

Question 29

_________is a form of energy which you produce the sensation of site

Answer 29

Light

Question 30

Distance between the pole and the principal focus of the spherical mirror is called

Answer 30

Focal length
F= R/2
R radius of curvature of mirror

Question 31

The angle of deviation depends on the refractive index of the glass

Answer 31

True

Question 32

The angle of deviation of light rays in a prism depend on the angle of

Answer 32

Incidence

Question 33

According to cartesian sign convention which mirror and which lens has negative focal length

Answer 33

Concave mirror and concave lens

Question 34

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.

Answer 34

-2 cm

Height of the image is -2 cm

Question 35

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.

Answer 35

Position of image -24cm