physics Gk Questions 2020-24

Physics

Q - Scientific study of the behaviour of light is called ?
Ans - Optics
Q - What is the time taken by light to reach earth from sum ?
Ans - 8 minutes 20 seconds
Q - Which phenonomenon proves that light is a transverse in nature ?
Ans - Polarisation of light
Q - Name the phenonomenon by which colour of sky appears as blue ?
Ans - Scattering of light
Q - Scattering of light is maximum in which colour ?
Ans - Violet colour
Q - Scattering of light is maximum in which colour ?
Ans - Red colour
Q - By which phenomenon sun looks reddish during sun rise and sunset ?
Ans - Scattering of light
Q - Any material which allow most of the incident light to pass through them are called ?
Ans - Transparent
Q - Ant material which allow some of the incident light to pass through them are called ?
Ans - Transparent
Q - Any material which do not allow incident light to pass through them are called ?
Ans - Opaque
Q - Object which emit light by themselves like sun stars are called ?
Ans - Luminous bodies
Q - Astronomer in space when look outside from spacecrafr the sky will appear ?
Ans - Black
Q - Object which do not emit light by themselves are called ?
Ans - Non luminous bodies
Q - Twinkling of stars is based on which phenomenon Ans - Refrection of light
Q - Swimming pool appear less deep than its actual depth is due to ?
Ans - Refrection of light
Q - Coin in bucket appear less deeper is due to which phenomenon ?
Ans - Refrection of light
Q - Stars in sky seems higher than they actualy are is due to which phenomenon ?
Ans - Refrection of light
Q - Why sun appear early before sun rise and after sunset ?
Ans - Due to refrection of light
Q - Writing on paper appears lifted when a glass slab is placed over the paper ?
Ans - Due to refrection of light
Q - what is the main condition for total internal Refrection ?
Ans - Light should be travel from denser medium rarer medium
Q - Sparkling of Diamond is due to which phenomenon ?
Ans - Total internal Reflection
Q - In summer an optical illusion Mirage or looming seen is based on which phenomenon ?
Ans - Total internal reflection
Q - Optical fibre in communication in based on which principal ?
Ans - Total Internal Reflection
Q - Kerosene oil spread on water surface appears to the coloured is due to ?
Ans - Interference of light
Q - Glittiering of soap bubbels is due to which phenomenon ?
Ans - Interference of light
Q - What is the nature of light ?
Ans - Light has dual nature (it behaves as both wave and particle)
Q - Splitting of white into the seven colour is called as ?
Ans - Dispersion of light
Q - Name the seven coloured formed from prism during dispersion of light ?
Ans - VIBGYOR ( Violet, indige, Blue, Green, Yellow, Orange & Red)
Q - During dispersion of light which colour of light deviates maximum ?
Ans - Violet.
Q - During dispersion of light which colour of light deviates minimum?
Ans - Red.
Q - Why leaves of tree appears green in colour?
Ans- Absord all colour and reflect green colour
Q - In which light rate of photosynthesis is maximum?
Ans - Red light.
Q - Which colour of light has maximum wavelength?
Ans - Red.
Q - Which colour of light has minimum wavelength?.
Ans - Violet.
Q - Our eyes has which type of lens ?
Ans - Convex
Q - Lamberts law is related to ?
Ans - Illumination
Q - Name the metal which is Best reflector of light
Ans - Silver
Q - Ant object which absorbs all colours and reflect no colour will appear ?
Ans - Black
Q - Why red light is used in traffic signals ?
Ans - Red colour light disperses least (and maximum wavelength)
Q - what is time taken by by light to reach earth from Moon ?
Ans - 1.28 seconds
Q - What is light ?
Ans - Light is a form of energy which is propagate electromagnetic wave
Q - Name the scientist who measured the speed of light ?
Ans - Olaus Roemer (1676)
Q - What are the two main type of Lens ?
Ans - Convex lens and concave lens
Q - What is the other name of convex lens ?
Ans - Converging lens
Q - What is the other name of concave lens ?
Ans - Diverging lens
Q - How many types of spherical Mirror ?
Ans - Concave Mirror
Convex Mirror
Q - Which type of mirror is used as shaving mirror ?
Ans - Concave mirror
Q - Which type of mirror is used in solar cooker ?
Ans - Concave mirror
Q - Which type of mirror is used as dentist mirror ?
Ans - Concave mirror
Q - Which type of mirror is used as rear view mirror in automobiles ?
Ans - Convex mirror
Q - Which type of mirror is used as Street light reflection ?
Ans - Convex mirror
Q - Which type of mirror is used as looking mirror in bathroom or dressing table ?
Ans - Plane mirror
Q - Which type of lens is thicker at the middle than at the edges ?
Ans - Convex lens
Q - Which type of lens is thicker at the edges than at the middle ?
Ans - Concave mirror
Q - What is reflective index ?
Ans - It is the ratio of speed of light in vaccum to the speed of light in medium
Q - Which type of colour is called primary colour ?
Ans - Blue, Red, Green
Q - What is secondary colour ?
Ans - Coloured produced by mixing any two primary colour
Q - How many secondary colours ?
Ans - 3 ( Yellow, magenta and cyan)
Q - On mixing Green colour and Red Colour formed is ?
Ans - Yellow
Q - On mixing Red Color and Blue Colour Result colour formed is ?
Ans - Magenta
Q - On mixing Blue colour and Green colour result formed is ?
Ans - Cyan
Q - According to law of reflection angle of incidence is always equal to the ?
Ans - Angle of reflection
Q - What is the full form of LASER ?
Ans - Light Amplification by Stimulated Emission of Radiation
Q - Name the optical instrument which is used to see the Small object which cannot be seen with naked eye ?
Ans - Microscope
Q - Which optical instrument is used to observe a distand object clearly
Ans - Telescope
Q - What is Snell's law or second law of reflection ?
Ans - The ratio of sine of angle of incidence to the sine of the angle of reflection is a constant
Sini/sinr =u
Q - What is reflective index ?
Ans - It is ratio of speed of light in vaccum to its speed in medium
Q - When ray of light moving from danser to rarer medium at an angle of incidence is greater than critical angle is called ?
Ans - Total internal reflection of light
Q - For ray of light to suffer total internal reflection it must passes from ?
Ans - Danser medium to rarer medium (Glass to water)
Q - Green leaves of tree viewed in red colour will appear ?
Ans - Black
Q - Indian scientist C V Raman awarded noble prize for ?
Ans - Scattering of light
Q - What is the radius of curvature of plane mirror ?
Ans - Infinity
Q - Which type of wave is used in night vision apparatus ?
Ans - Infrared waves
Q - Air bubbles in the water acts like a which type of lens ?
Ans - Concave lens
Q - Colour of visible light is related on which parameter ?
Ans - Amplitude
Q - In photography camera which type of lens is used ?
Ans - Convex lens
Q - Name the scientist who invented electron microscope ?
Ans - Knoll and ruska
Q - What is used for splitting of white light into seven colour ?
Ans - Prism
Q - Name the instrument is used to study the dispersion of light ?
Ans - Spectrometer
Q - Eclipse occur due to which phenomenon of light ?
Ans - Rectilinear propogation
Q - when ray of light travelling from one medium to another its ?
Ans - Frequency remains same
Q - We see the image of our face when we look into the mirror ?
Ans - Reflection
Q - Light year is a unit of ?
Ans - Distance
Q - A laser beam is always ?
Ans - A parallel beam
Q - Energy associated with light depends on ?
Ans - It's frequency
Q - What is the power of lens ?
Ans - Dioptre
Q - Least distance for clear vision of normal eye is ?
Ans - 25 cm