The sky from moon appears black. Why?

1 Answer

Answer :

Ans: as the moon has no atmosphere, so the sky looks completely black when viewed from the moon.

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Description : A geostationary satellite appears standstill to a viewer on the equator of earth.

Last Answer : Ans: Because the distance remains the same.

Description : The Sun appears red at sunset and sunrise. Why?

Last Answer : Ans: The sun appears red at the time of sunset and sunrise due to the scattering of light by small particles of dust or smoke near the surface of the earth. The light travels relatively without hindrance that is why the sun appears red at the time of sunset and sunrise.

Description : Rainbow is produced in the sky after rainfall and sunlight.

Last Answer : Ans: After rain, many droplet of water travel in the atmosphere. When sun rays fall on these droplets, dispersion of water occurs and droplets act as prism and produce a spectrum of seven colours. That’s why a rainbow is seen in the sky after rain.

Description : Earth is continuously pulling moon towards its centre. Why does not the moon fall on to the earth?

Last Answer : Ans: it is so because the gravitational attraction of the earth provides the necessary centripetal force to the moon for its orbital motion around the earth due to which the moon is revolving around the earth.

Description : What is a black hole? Why is it called so?

Last Answer : Ans: A black hole is a super dense planetary material formed due to the death of a star of mass more than five solar masses. It is called black hole because any particle or photon approaching its surface is just swallowed by it. It appears black, as radiation is neither emitted nor reflected by it.

Description : Why is petroleum often called black gold?

Last Answer : Ans: Petroleum is often called black gold because of its great demand in the modern industry and for domestic use. It provides fuel for heat and lighting, lubricant for machinery and raw material for a number of industries.

Description : Light colours absorb less heat therefore these are not heated as much as the black colour.

Last Answer : Ans: Dark colours do not exactly absorb more heat, but they do convert a higher percentage of light into heat. In the sun with a dark coloured shirt it gets hot, where a lighter ... and converted into heat. White objects reflect all visible light, where black objects absorb all visible light.

Description : To an astronaut in the spacecraft, the sky colour appears to be (a) Blue (b) White (c) Black (d) Orange red

Last Answer : Ans:(c)

Description : In absence of atmosphere, the colour of sky appears (a) blue (b) black (c) red (d) yellow

Last Answer : (b) black

Description : What causes milk to rise up when we boil it?

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Description : How does a compact fluorescent lamp consume less electricity than conventional fluorescent lamps and bulbs?

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Description : Why does an egg (with the shell) burst when cooked in a microwave oven?

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Description : Why is fuel used in airplanes different from those used in motor vehicles?

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Description : How does a rechargeable battery work? What is the life of such batteries and how are they different from ordinary batteries?

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Description : How is a ventriloquist able to throw his voice?

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Description : How do touch screens work?

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Last Answer : Solar wind contains intense clouds of high energy particles which are produced by solar storms. These clouds of particles affect Earth. These clouds are called coronal mass ejections. They reach the earth ... by the solar wind, especially the storm clouds that the Sun launches our way very often.

Description : Why is the @ symbol used in an email address?

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Description : What is Polaroid sunglasses made of?

Last Answer : ANSWER I: Polaroids are thin and large sheets of crystalline polarising material (made artificially) capable of producing plane polarised beams of large cross section. As early as 1852, it was ... to return to their original shape, resulting in the loss of their light absorbing properties.

Description : Why does rain come in drops and not in a continuous stream?

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Description : Why is the Earth's core hot? What caused it to heat up? Is it still heating, or now cooling?

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Description : How is carbon dioxide removed from blood before it is exhaled?

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Description : How do certain species of birds such as Humming Birds, Terns, Gulls and Kestrels remain in the air without a forward motion?

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Description : How does ballast-less track provide safe travel?

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Description : What is Computer Simulation Technique?

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Description : Do animals also have blood groups like humans?

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Description : Why does sea water not erode coastal areas in all places?

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Description : How does scratching cure itching sensation?

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Description : How is sex determined in dioecious plants?

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Description : Why is fire hot?

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Description : How do icebergs form?

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Description : How does the solar wind affect Earth?

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