GROWTH DEVELOPMENT CHILD
SUMMATIVE ASSESSMENT
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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very cold
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moving towards us
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dying
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about to supernova
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Detailed explanation-1: -When an object is moving away from us, the light from the object is known as redshift, and when an object is moving towards us, the light from the object is known as blueshift.
Detailed explanation-2: -"Blueshift” is a term that astronomers use to describe an object that is moving toward another object or toward us. Someone will say, “That galaxy is blueshifted with respect to the Milky Way", for example. It means that the galaxy is moving toward our point in space.
Detailed explanation-3: -Some of the nearest stars, such as Barnard’s Star, are moving towards us and hence show a ‘blueshift’ (their light is shifted towards shorter wavelengths). Even some galaxies (for example, the Andromeda Galaxy) are blueshifted.
Detailed explanation-4: -As an object moves towards us, sound and light waves are bunched up, so the pitch of the sound is higher, and light waves are moved towards the blue end of the electromagnetic spectrum, where light has a shorter wavelength. In the case of light waves, this is called blueshift.
Detailed explanation-5: -Doppler shift So, if a star is moving towards Earth, it appears to emit light that is shorter in wavelength compared to a source of light that isn’t moving. Because shorter wavelengths correspond to a shift towards the blue end of the spectrum, this is called blueshift.