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NATS 1870- Questions and Answers (Expert
Solutions)
Q: Earth's atmosphere according to increasing altitude? ANS 🗹🗹: Ionosphere,
mesosphere, stratosphere, clouds, troposphere
Q: Sort the stars by their temperature from cold to hot ANS 🗹🗹: Blue, violet, yellow,
red
Q: Principles of specular reflection? ANS 🗹🗹: Object whose image is formed by a flat
mirror is = real
Angle of incidence = angle of reflection
Image by reflection in flat mirror = virtual
The normal = 90 degrees
Q: Blackbody curves of 4 stars at different temperatures, match to B-V colour index?
ANS 🗹🗹: Star 1: 0.70
Star 2: 1.25
Star 3: 1.70
Star 4: 1.85
Q: Absolute zero is a term referring to? ANS 🗹🗹: All of these: the temperature at which
subatomic motion is at minimal, -273°C, the temperature at which an object will radiate
least amount of energy
Q: In an atom, absorption is the process where? ANS 🗹🗹: An electron is boosted to a
higher energy orbital
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Q: During a record-setting heat wave in 2016 in India, asphalt-paved roads were so hot
that they actually melted people's shoes on contact, getting them stuck to the pavement.
Why would this be far less likely to happen with roads/sidewalks made of concrete
slabs instead? ANS 🗹🗹: Light grey concrete slabs would absorb much less of the
incoming light than black asphalt
Q: The accurate explanation and confirmation of how aroura are produced came from?
ANS 🗹🗹: Russian and American satellites measuring activity around earths space
neighbourhood
Q: Which of the following is NOT an advantage that a reflector telescope has over a
refractor telescope? ANS 🗹🗹: A reflector doesn't have to deal with the twinkling of the
stars caused by the turbulence of air on earth, as a reflector does
Q: Although Alhazen correctly viewed light as bouncing off objects in all outward
directions, why did he include only the central ray as entering the eye? ANS 🗹🗹: He did
not know the eye could bend other non-central rays
Q: Which of these examples corresponds to Alhazen's description of how we can "see"
external objects? ANS 🗹🗹: Intromission: light rays bounce off objects, then travel in
straight lines to our eyes
Q: Anaxagoras and Empedocles were the first ones to correctly suggest that ANS 🗹🗹:
Darkness is simply the absence of light
Q: In the diagram below, according to the principle of specular reflection, which angles
are equal? ANS 🗹🗹: Both B=C and A=D
Q: What was the role of the "transparent medium" in Aristotle's theory of vision? ANS
🗹🗹: Colours of objects traveled through the transparent medium to enter our eyes
Q: When it comes to considering building a new telescope on the ground to observe the
universe afar, which of the specific wavelengths observing telescopes below would be
most successful? ANS 🗹🗹: Visible light and radio waves telescopes
NATS 1870- Questions and Answers (Expert
Solutions)
Q: Earth's atmosphere according to increasing altitude? ANS 🗹🗹: Ionosphere,
mesosphere, stratosphere, clouds, troposphere
Q: Sort the stars by their temperature from cold to hot ANS 🗹🗹: Blue, violet, yellow,
red
Q: Principles of specular reflection? ANS 🗹🗹: Object whose image is formed by a flat
mirror is = real
Angle of incidence = angle of reflection
Image by reflection in flat mirror = virtual
The normal = 90 degrees
Q: Blackbody curves of 4 stars at different temperatures, match to B-V colour index?
ANS 🗹🗹: Star 1: 0.70
Star 2: 1.25
Star 3: 1.70
Star 4: 1.85
Q: Absolute zero is a term referring to? ANS 🗹🗹: All of these: the temperature at which
subatomic motion is at minimal, -273°C, the temperature at which an object will radiate
least amount of energy
Q: In an atom, absorption is the process where? ANS 🗹🗹: An electron is boosted to a
higher energy orbital
, Page | 2
Q: During a record-setting heat wave in 2016 in India, asphalt-paved roads were so hot
that they actually melted people's shoes on contact, getting them stuck to the pavement.
Why would this be far less likely to happen with roads/sidewalks made of concrete
slabs instead? ANS 🗹🗹: Light grey concrete slabs would absorb much less of the
incoming light than black asphalt
Q: The accurate explanation and confirmation of how aroura are produced came from?
ANS 🗹🗹: Russian and American satellites measuring activity around earths space
neighbourhood
Q: Which of the following is NOT an advantage that a reflector telescope has over a
refractor telescope? ANS 🗹🗹: A reflector doesn't have to deal with the twinkling of the
stars caused by the turbulence of air on earth, as a reflector does
Q: Although Alhazen correctly viewed light as bouncing off objects in all outward
directions, why did he include only the central ray as entering the eye? ANS 🗹🗹: He did
not know the eye could bend other non-central rays
Q: Which of these examples corresponds to Alhazen's description of how we can "see"
external objects? ANS 🗹🗹: Intromission: light rays bounce off objects, then travel in
straight lines to our eyes
Q: Anaxagoras and Empedocles were the first ones to correctly suggest that ANS 🗹🗹:
Darkness is simply the absence of light
Q: In the diagram below, according to the principle of specular reflection, which angles
are equal? ANS 🗹🗹: Both B=C and A=D
Q: What was the role of the "transparent medium" in Aristotle's theory of vision? ANS
🗹🗹: Colours of objects traveled through the transparent medium to enter our eyes
Q: When it comes to considering building a new telescope on the ground to observe the
universe afar, which of the specific wavelengths observing telescopes below would be
most successful? ANS 🗹🗹: Visible light and radio waves telescopes
