Why does the sky appear dark instead of blue to an astronaut?
When the sunlight passes through the atmosphere, the fine particles scatters in the atmospheric layers blue light will appear having shorter wavelength and the red light having the larger wavelength. The scattered blue light enters to our eyes if we see the sky from the earth.
The sky does not appear blue to an astronaut because there is no atmosphere in the space and hence the light does not scatter into the various colours as like when we see the colours of sun or sky from the earth. If there is no scattering occurs, the sky will look dark to the astronaut from the space.
Popular Questions of Class 10 Science
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When a 12 V battery is connected across an unknown resistor, there is a current of 2.5 mA in the circuit. Find the value of the resistance of the resistor.
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Outline a project which aims to find the dominant coat colour in dogs.
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Draw the structure for the following compounds.
(i) Ethanoic acid (ii) Bromopentane*
(iii) Butanone (iv) Hexanal.*Are structural isomers possible for bromopentane?
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A hot plate of an electric oven connected to a 220 V line has two resistance coils A and B, each of 24 Ω resistance, which may be used separately, in series, or in parallel. What are the currents in the three cases?
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(a) What property do all elements in the same column of the Periodic Table as boron have in common?
(b) What property do all elements in the same column of the Periodic Table as fluorine have in common? - Q:-
Calculate the number of electrons constituting one coulomb of charge.
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What is an homologous series? Explain with an example.
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A man with blood group A marries a woman with blood group O and their daughter has blood group O. Is this information enough to tell you which of the traits – blood group A or O – is dominant? Why or why not?
Recently Viewed Questions of Class 10 Science
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Find the focal length of a convex mirror whose radius of curvature is 32 cm.
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Do basic solutions also have H+(aq) ions? If yes, then why are these basic?
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Find out, from Table 10.3, the medium having highest optical density. Also find the medium with lowest optical density.
Material
mediumRefractive
indexMaterial
mediumRefractive
indexAir 1.0003 Canada
Balsam1.53 Ice 1.31 Water 1.33 Rock salt 1.54 Alcohol 1.36 Kerosene 1.44 Carbon
disulphide1.63 Fused
quartz1.46 Turpentine
oil1.47 Ruby 1.71 Benzene 1.50 Sapphire 1.77 Crown
glass1.52 Diamond 2.42 Table 10.3 Absolute refractive index of some material media
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How is the equal genetic contribution of male and female parents ensured in the progeny?
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An electric iron of resistance 20 Ω takes a current of 5 A. Calculate the heat developed in 30 s.
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Outline a project which aims to find the dominant coat colour in dogs.
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(i) Write the electron-dot structures for sodium, oxygen and magnesium.
(ii) Show the formation of Na2O and MgO by the transfer of electrons.
(iii) What are the ions present in these compounds?
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Which one of the following types of medicines is used for treating indigestion?
(a) Antibiotic
(b) Analgesic
(c) Antacid
(d) Antiseptic - Q:-
How is the amount of urine produced regulated?
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