Why does a black board appears black in color? (1) It reflects black color (2) It absorbs black color (3) It reflects all colors (4) It absorbs all the colours

1 Answer

Answer :

(4) It absorbs all the colors Explanation: When white light falls on an opaque body, it absorbs all the colors except one color which it reflects; this reflected color is the color of the body.

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Description : An object which absorbs all colours and reflects none appears: (1) White (2) Grey (3) Blue (4) Black

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Description : An object which absorbs all colours and reflects none appears: (1) white (2) grey (3) blue (4) black

Last Answer : black

Description : An object which absorbs all colours and reflects none appears:

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Description : What is the color of an object that reflects all the colors of light ?

Last Answer : The color of an object that reflects all the colors of light is white.

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Last Answer : (2) the temperature inside the Earth is higher than the atmospheric temperature

Description : The water from a hand pump is warm in winter because - (1) Our body is cold in winter and the water appears to be warm (2) The temperature inside the earth is higher than the atmospheric ... causes friction which warms up the water (4) Inside water comes out and absorbs heat from the environment

Last Answer : (2) The temperature inside the earth is higher than the atmospheric temperature Explanation: In winter, the outside temperature is lower than that of water flowing out of the pump, and therefore, the ... the outside temperature is higher than the water of the pump, and therefore, it feels cold.

Description : The water from a hand pump is warm in winter because - (1) Our body is cold in winter and the water appears to be warm (2) The temperature inside the earth is higher than the atmospheric ... causes friction which warms up the water (4) Inside water comes out and absorbs heat from the environment

Last Answer : (2) The temperature inside the earth is higher than the atmospheric temperature Explanation: In winter, the outside temperature is lower than that of water flowing out of the pump, and therefore, the ... the outside temperature is higher than the water of the pump, and therefore, it feels cold.

Description : The water from a hand pump is warm in winter because (1) Our body is cold in winter and the water appears to be warm (2) The temperature inside the earth is higher than the atmospheric ... causes friction which warms up the water (4) Inside water comes out and absorbs heat from the environment

Last Answer : The temperature inside the earth is higher than the atmospheric temperature

Description : The sky appears blue because – (1) All colours interfere to produce blue (2) In white light, the blue component dominates (3) The atmosphere scatters blue colour more than the others (4) It is actually blue

Last Answer : (3) The atmosphere scatters blue colour more than the others Explanation: Diffuse sky radiation is solar radiation reaching the Earth's surface after having been scattered from the direct solar beam by ... the atmosphere (approximately 25% of the incident radiation when the sun is high in the Sky.

Description : Sun appears red in colour at sun-rise and sunset due to – (1) the fact that sun emits only red colour at that time (2) red light having longer wave length scatters away (3) that sun Comes out of the mountains (4) that all other colours scatter away except red

Last Answer : (4) that all other colours scatter away except red Explanation: According to Rayleigh's law, the intensity of scattered light varies inversely as the fourth power of its wavelength. Sunlight consists of ... have to travel a larger part of the atmosphere because they are very close to the horizon.

Description : Sun appears red in colour at sunrise and sunset due to (1) the fact that sun emits only red colour at that time (2) red light having longer wave length scatters away (3) that sun comes out of the mountains (4) that all other colours scatter away except red

Last Answer :  that all other colours scatter away except red

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Last Answer : the atmosphere scatters blue colour more than the others

Description : An object which absorbs all colours ap- pears as?

Last Answer : Black

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Last Answer : Ans:(d)

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Last Answer : (2) the temperature inside the Earth is higher than the atmospheric temperature

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Description : The sky appears blue because the earth’s atmosphere _____? A. Scatters blue light B. Transmits blue light C. Reflects blue light D. Has actual blue cover

Last Answer : ANSWER: C

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Description : Why does a black board appears black in colour?

Last Answer : It absorbs all the colours

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Description : A body absorbs heat most if it is (1) black and rough (2) black and smooth (3) white and rough (4) white and smooth

Last Answer : black and rough

Description : A ray of white light strikes the surface of an object. If all the colours are reflected, the surface would appear (1) Black (2) White (3) Grey (4) Opaque

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Description : A colour-blind person cannot – (1) See distant objects (2) See black colour (3) Distinguish between certain colours (4) Have persistence of vision

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Description : The ringing of an electric bell in an enclosed evacuated glass bell jar is not heard outside because - (1) the ringing is not loud enough (2) the glass of the bell jar absorbs the sound waves (3) the bell jar is too small (4) there is no air or any other gas in the bell jar

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Last Answer : ANSWER: X -- PLUTONIUM-239

Description : Sound is heard over longer distances on rainy days because (1) sound travels slowly in moist air (2) sound travels faster in moist air (3) moist air does not absorb sound (4) moist air absorbs sound

Last Answer : sound travels faster in moist air

Description : An egg sinks in soft water but floats in a concentrated solution of salt because (1) egg absorbs salt from the solution and expands (2) albumin dissolves in salt solution and egg becomes lighter (3) the density of salt solution exceeds the density of eggs (4) water has high surface tension

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