Light

Question 1

Study of light

Answer 1

Optics, light travelled in the form of transverse ways, emw
Velocity of light in vaccum 3 lkh km/ sex
Distance bt sun and earth 15 crore that is travelled in 8 mins sun rays coming to earth fastest moving
186287 miles per second

Question 2

Velocity of light measured by

Answer 2

Romar

Question 3

Corposecular theory

Answer 3

Newton
First theory of light
Light travelled in the form of particles ,
Velocity of light more in denser than rarer but now present light is more in rarer and less in denser

Question 4

Wave theory of light

Answer 4

Huygens
In the form of waves
More in rarer and less in denser
Light required medium called eather

Question 5

Electro magnetic theory of light

Answer 5

Maxwell, light does not required medium for their propogation

Question 6

Quantum theory of light

Answer 6

Max Planck, travelled in the form of packets pr bundles,

Question 7

Modern theory of light

Answer 7

It has dual nature
Particle and wave.
Light doesn’t require any medium for their propogation
Velocity of light more in rarer medium lesser than rarer medium
Vaccum> gases>liquids>solids

Question 8

Light travels more

Answer 8

Vaccum >gases>liquids>solids
Above the method we can identify the which is denser and which is rarer hence by comparing two of it in which medium light has travelled more is called rarer and which medium it has travelled less called denser

Question 9

Infra red rays

Answer 9

Proposed by harshals
Physiotherapy
Tv remote
Taking photos in dark
Released from hot bodies sun heater welding machine soldering gun, it rays will be released
Bolometer is used to detect the it rays
Sunglass or cooling glass observe the ir
rays
Rock salt glass not absorb the ir rays

Question 10

Microwave

Answer 10

Discovered by hertz
Used in micro oven
Artificial communication system, radar
Magnatron is used to detect the micro waves,
Radar radio detection and ranging
UnIdentified objects are detected by the radar

Question 11

Radio waves

Answer 11

Radio waves are discovered by marconi
Radio waves used in Wireless telecommunication system

Question 12

Uv rays

Answer 12

Ultra violet rays
Proposed by ritter,
To detect Fake currency and fake documents
Uv rays emits from the hot objects like sun and hot weldings. Direct uv rays are protect by ozone layer dabson discovered
Depletion of ozone layer paramin identified
Freon gas is used as Coolant in rfrig and acs ccl2f2
Dichloro difloro methane
October 16 world Food day
Ozone mixed in mineral water

Question 13

X rays

Answer 13

X rays are discovered by rantajen
X rays ante unknown
Edo anukunte edo rays vachai so let us x
Soft x rays radio graphy
Hard x rays to check the luggages in airport
To check metal quality

Question 14

Gamma rays

Answer 14

Henry becqueral
They high penetrating power
X rays are used in cancer treatment to kill the cancer cells
Thery are generally emitted at the time of nuclear explosion black hole formation

Question 15

Reflection of the light

Answer 15

The bouncing back of the light within a same medium when light falls on the same medium in different direction
Laws of reflection I, n, r are in same plane
Angle of incidence is equal to angle of reflection
Mirrors are 2 types
Plain
Spherical

Question 16

Plain mirror

Answer 16

Inside and outside of the plain mirror
Outside the mirror what we laid is called object and what we laid inside the mirror Is called image
Oka object kanipisthundi ante rendu jaragali, chair kanipisthundi ante light padthundi dani meda light padithe adi absorb cheskokunda reflect cheyali apude avi na eyes dagariki vachi cherithe apuduu naku kanipinchinattu
Konni lakshalu vasthaii alanti rays kani
Rendu rays teskunta
Incident ray, incident ray plain mirror meds vesa ante emaidddi adi reflect ayyiii venakki vasthadii ala reflect aina rays anni ekkadiathe meet avuthayaoo akkade image form avuddii

Question 17

Virtual and erected images means

Answer 17

If images are formed inside the mirror called virtual and erected images
Our images not formed on formed it formed certain distance so it is called virtual and erect ( midya and nituruga unna images)

Question 18

If the images are formed outside the mirror called

Answer 18

Real and invert images, nija mariyu talakindulu

Question 19

In plain mirrors always formed

Answer 19

Virtual and erected images are formed
Lateral inversion images are formed ( left right and right light are formed)
Total 11 alphabets are symmertrical
A HIMO TUVWXYZ
A person stands in front of plane mirror 6 feets the minimum heightbof thr required to complete images is half of the object

Question 20

In a plain mirror a man running towards to the mirror or away from the mirror the velocity v

Answer 20

In mirror it appears 2v

Question 21

If 2 plane mirrors kept with some angle the number of reflections formed are

Answer 21

N= 360 / angle
If even number came then do even-1
If odd came no problem it’s odd number

Question 22

Periscope

Answer 22

Reflection of light waves on a plain mirror is called periscope
Refcted rays anevi incident ray anedi palin mirror loki velthundi akkada nundi neruga mana human eye ki reach avhthundi danne periscope ani antaru

Question 23

Spherical mirrors

Answer 23

It’s look like a globe cut one side danni ela aina use cheskovachu convex or concave, cocave outside pootha poosthe danni concave guha la untadiii, okavela lopala pootha pusam anukoo danni convex antaruuu manam ela aina marchukovachu annamataa

Question 24

Concave mirror and convex mirror

Answer 24

Outside concave
Inside convex
Both has centre ( imaginary lo undi kabatti dani centre of curvature ani antaru , every sphere has a centre called centre of curvature p and pole
Centre of curvature and pole ni kaluputhu oka line geestam danni principle axis ani antam, centre of curvature and pole ki madyalo focus ani anukuntamu, so general c to p called radius of curvature, focus and pole and called focal length

Question 25

Images formed by the concave mirror

Answer 25

If the images kept in infinity distance the object image formed at focus, if the object kept behind c image formed between c and f If the object is kept at c the image formed on c only If the object kept between c and f the images formed behind the c If the object is kept on the foci, the image formed at infinite distance If the object is kept between f and p then the image formed inside the mirror

Question 26

Uses of concave mirror

Answer 26

Torch light Search light Solar cookers Makeup mirror Shaving mirror Vehicles headlight. Dentist ent doctor. Anothers name of concave mirror concave mirror

Question 27

Images formed by the convex mirror

Answer 27

Only two cases If object kept at infinity outside of the mirror image formed at foci If object kept near to the mirror the image formed between pole and foci Rear view mirror of the vehicles, side view mirror, What ever image formed inside virtual and erect Whatever image formed outside the image called real and invert

Question 28

Refraction of light

Answer 28

Light travels in straight line danne rectilinear propogation antaru , konni konni light bend ayi travel chestafi, the bending of light or change the direction of light when enters one medium to another medium That is called refraction of light Cool drink lo straw pettinapufuu vanginattu kanipisthadi Hand fingers ni lopaliki pettinapufuu pottiga kanipisthundi Swimming pool length takkuva ga unnati, Coin lopala veste paiki unnattu anipisthadi, Disti nimmakalayani vestaru water lo vesthe peddaga kanipisthaffi daniki reason adhey Air water ki madya inter face undi oka imaginary line perdicular ga geesa, torch light incident ray vesa, when light enters air to water then the refracted ray bend towrds the normal,

Question 29

Refraction

Answer 29

Angle of uncidence greater than angle of refraction, rarer to deser medium Ala kaunda nenu jebulo torch light petkoni kinda water lo ki poyi akkada nundi air loki light veste light travels from denser to rarer apuduu emaidddi ante normal geesukuntam kada imaginary line daniki away ga pothundi, ah time lo incident ray is less than the refracted ray when light enters denser to rarer

Question 30

Laws of refraction

Answer 30

I n r in same plane Snells law, sin I / sin r What is refractive index How much bending of the light one medium to another

Question 31

Rafractive index

Answer 31

Air 1.0003( 3 Water 1.3( 2.25 Glass 1.5( 2 Diamond 2.42(1.2 Diamond has high refractive index

Question 32

Diff between convex and concave lens

Answer 32

Covex both are curved outwards Middle part thick, edhes thin Converging lens, concave mirror converging mirror so convex lens convergin Positive lens Concavr both are curved inwards, middle part thin and edges thick Concave lens are diverging lens Negative lens

Question 33

Interference of the light

Answer 33

Oka light pothunte dani place loki inkoti velluddi light ways okadanitho okati involve ainapuduu different different colours vasthai, Beautiful colours seen on a soap bubbles and oil films

Question 34

Diffraction of light

Answer 34

Light bend avuddi ani anukunam refraction lo edges dagara Edges of the doors and windows nundi lopalaiki ravadam chusthuntam danne diffraction antam, Cd meda different colours kanipisthaii danne manma diffraction antam Beautiful colours on CD

Question 35

Scatterinh of light

Answer 35

Indian scientist sir cv raman 1928 feb 26 . He explained the scattering of light known as raman effect he got noble prize in 1930 , em cheppadu ante This sky appears as blue in colour The clouds appear as white in colour Sun appears brilliant red colour before dawn and dusk The sky appears black in colour when it is seen from the space,

Question 36

Disperssion of kight

Answer 36

When a ray travells through prism then split into 7 colurs Violet most dangerous to human eye Indigo deoes not appear in rainbow Blue highly scattered colour. Green peace and happiness to human eyes Yellow middle colour Red highest wavelength Kinda nundi oaiki velthunatunaouduu energy peruguddii and wavelength kuda peruguddiiia kani velocity anedi annitlo equal ga untadii Exact shape of rainbow is spherical shape, only observed by the pilots Water bubble act as a prism It is formed opposite to the sun Primary rainbow, 42 ° tho padithe Light anedi oka medium nundi inko medium loki vellali ante first refraction jaragali, okasari total internal reflection jaruguthundi, jarigina tarvatha 7 colours la split avuthundi, Vibgyor, 1 refraction 2 total internal reflection 3 dispersion jaruguthundi Secondary rainbow Okasari refraction jaruguthundi 2 times total internal reflection jaruguthundi tarvatha 7 colours firm avuthai vibgyor kinda nundi kakunda pain nundi vasthai

Question 37

Total internal reflection

Answer 37

Light enters from denser medium to rarer medium The angle of incidence greater than the critical angle Mirages Diamond glitters working of endoscopy notlo pipe vestaruu gastric pootha posinda leda chustharu Kelanoscopy Working of opticak fibre invented by pm Narendra singh kapani

Question 38

Polarization of light

Answer 38

Non polarised light can be convertrr into polarised light, with the help of polaroids it can be split into any direction, Polarised glasses travels in one direction Non polarised travels in different direction The concept used in 3 d pictures Holography Light traveeled in the form of transsverse waves

Question 39

What images are formed in microscope

Answer 39

Colours are 2 types Primary Secondary Green meganta. Blue yellow. Red cyan General manager ki accident aithe valla office boy vachi red cells ekkinchadu Complementary colour of green Meganta Complementary colour of blue. Yellow Complementary colour of the red Cyan When red colour rose seen in blue or green colour light it appears as a black

Question 40

Microscope

Answer 40

Simple antony waana lewan hoek Convex lens single Virtual erected magnified. Compound Concex lens 2 Virtual inverted and magnified

Question 41

Telescope

Answer 41

Astronomical telescope Convex lens 2 . Virtual inverted and magnified Terristrial telescope. Convex lens 3 Virtual Erected Diminihed