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Consider the following statements regarding asteroids: - Asteroids are rocky debris of varying sizes orbiting the Sun
- Most of the Asteroids are small but some have diameter as large as 1000 km
- The orbit of asteroids lies between the orbits of Jupiter & Saturn
Which of the statements given above is/are correct?- a)1,2 and 3 are correct
- b)2 and 3 are correct
- c)1 and 2 are correct
- d)1 and 3 are correct
Correct answer is option 'C'. Can you explain this answer?
Consider the following statements regarding asteroids:
- Asteroids are rocky debris of varying sizes orbiting the Sun
- Most of the Asteroids are small but some have diameter as large as 1000 km
- The orbit of asteroids lies between the orbits of Jupiter & Saturn
Which of the statements given above is/are correct?
a)
1,2 and 3 are correct
b)
2 and 3 are correct
c)
1 and 2 are correct
d)
1 and 3 are correct
|
Wyatt Turner answered |
Understanding Asteroids
Asteroids are fascinating celestial objects that play a significant role in our solar system. Let's delve into the statements provided and clarify their correctness.
Statement 1: Asteroids are rocky debris of varying sizes orbiting the Sun
- This statement is correct.
- Asteroids are indeed composed of rock and metal, and they orbit the Sun, primarily found in the asteroid belt between Mars and Jupiter.
Statement 2: Most of the asteroids are small but some have a diameter as large as 1000 km
- This statement is also correct.
- While the majority of asteroids are small, with many being just a few meters in diameter, some larger asteroids, such as Ceres, have diameters that can reach up to 1000 km.
Statement 3: The orbit of asteroids lies between the orbits of Jupiter & Saturn
- This statement is incorrect.
- The majority of asteroids are located in the asteroid belt, which lies between the orbits of Mars and Jupiter. Saturn's orbit is much further out.
Conclusion
Based on the evaluations:
- Statement 1: Correct
- Statement 2: Correct
- Statement 3: Incorrect
Thus, the correct answer is option C (1 and 2 are correct). The statements about asteroids highlight their nature and size accurately, while the misconception about their orbits is clarified.
Asteroids are fascinating celestial objects that play a significant role in our solar system. Let's delve into the statements provided and clarify their correctness.
Statement 1: Asteroids are rocky debris of varying sizes orbiting the Sun
- This statement is correct.
- Asteroids are indeed composed of rock and metal, and they orbit the Sun, primarily found in the asteroid belt between Mars and Jupiter.
Statement 2: Most of the asteroids are small but some have a diameter as large as 1000 km
- This statement is also correct.
- While the majority of asteroids are small, with many being just a few meters in diameter, some larger asteroids, such as Ceres, have diameters that can reach up to 1000 km.
Statement 3: The orbit of asteroids lies between the orbits of Jupiter & Saturn
- This statement is incorrect.
- The majority of asteroids are located in the asteroid belt, which lies between the orbits of Mars and Jupiter. Saturn's orbit is much further out.
Conclusion
Based on the evaluations:
- Statement 1: Correct
- Statement 2: Correct
- Statement 3: Incorrect
Thus, the correct answer is option C (1 and 2 are correct). The statements about asteroids highlight their nature and size accurately, while the misconception about their orbits is clarified.
(Assertion): To orbit around the Sun, the planet Mars takes lesser time than the time taken by the Earth
(Reason): The diameter of the planet Mars is less than that of the Earth- a)Both A are R are true R is the correct explanation of A
- b)Both A and R are true but R is not a correct explanation of A
- c)A is true but R is false
- d)A is false but R is true
Correct answer is option 'D'. Can you explain this answer?
(Assertion): To orbit around the Sun, the planet Mars takes lesser time than the time taken by the Earth
(Reason): The diameter of the planet Mars is less than that of the Earth
(Reason): The diameter of the planet Mars is less than that of the Earth
a)
Both A are R are true R is the correct explanation of A
b)
Both A and R are true but R is not a correct explanation of A
c)
A is true but R is false
d)
A is false but R is true
|
Evan Parker answered |
Assertion:
To orbit around the Sun, the planet Mars takes lesser time than the time taken by the Earth.
Reason:
The diameter of the planet Mars is less than that of the Earth.
---
Explanation:
- The assertion is false because the time taken by a planet to orbit around the Sun is not directly related to its diameter. The time taken to complete one orbit, or its orbital period, is determined by the planet's distance from the Sun and its orbital speed.
- While Mars does have a smaller diameter than Earth, its distance from the Sun is also greater. This means that Mars has a longer orbital period compared to Earth. In fact, Mars takes about 687 Earth days to complete one orbit around the Sun, while Earth only takes about 365 days.
- Therefore, the reason given in the assertion is not a correct explanation for why Mars takes lesser time to orbit around the Sun compared to Earth.
---
So, option 'D' is the correct answer: A is false but R is true.
To orbit around the Sun, the planet Mars takes lesser time than the time taken by the Earth.
Reason:
The diameter of the planet Mars is less than that of the Earth.
---
Explanation:
- The assertion is false because the time taken by a planet to orbit around the Sun is not directly related to its diameter. The time taken to complete one orbit, or its orbital period, is determined by the planet's distance from the Sun and its orbital speed.
- While Mars does have a smaller diameter than Earth, its distance from the Sun is also greater. This means that Mars has a longer orbital period compared to Earth. In fact, Mars takes about 687 Earth days to complete one orbit around the Sun, while Earth only takes about 365 days.
- Therefore, the reason given in the assertion is not a correct explanation for why Mars takes lesser time to orbit around the Sun compared to Earth.
---
So, option 'D' is the correct answer: A is false but R is true.
(Assertion): The same face of the Moon is always presented to the Earth
(Reason): The Moon rotates about its own axis in 231/2 days which is about the same time that it takes to orbit the Earth- a)Both A are R are true R is the correct explanation of A
- b)Both A and R are true but R is not a correct explanation of A
- c)A is true but R is false
- d)A is false but R is true
Correct answer is option 'C'. Can you explain this answer?
(Assertion): The same face of the Moon is always presented to the Earth
(Reason): The Moon rotates about its own axis in 231/2 days which is about the same time that it takes to orbit the Earth
(Reason): The Moon rotates about its own axis in 231/2 days which is about the same time that it takes to orbit the Earth
a)
Both A are R are true R is the correct explanation of A
b)
Both A and R are true but R is not a correct explanation of A
c)
A is true but R is false
d)
A is false but R is true
|
Skylar Wright answered |
Understanding the Assertion and Reason
The assertion states that the same face of the Moon is always presented to the Earth. This is indeed true. The Moon is in synchronous rotation with Earth, meaning it takes the same amount of time to rotate on its axis as it does to orbit the Earth.
Explanation of the Assertion
- The Moon completes one full rotation on its axis approximately every 27.3 days.
- It also takes about 27.3 days to complete one orbit around the Earth.
- This synchronized motion is why we always see the same side of the Moon from Earth.
Evaluating the Reason
- The reason provided states that the Moon rotates about its own axis in 231/2 days.
- This duration is inaccurate; the correct period is approximately 27.3 days, not 231/2 days.
- Therefore, while the reason's concept is aligned with the assertion, the specifics are incorrect.
Conclusion
- The assertion is true as it correctly describes the Moon's synchronous rotation.
- The reason is false due to the incorrect duration of the Moon's rotation period.
Thus, the correct option is C: the assertion is true, but the reason is false. This distinction clarifies the relationship between the two statements, reinforcing the importance of accuracy in scientific explanations.
The assertion states that the same face of the Moon is always presented to the Earth. This is indeed true. The Moon is in synchronous rotation with Earth, meaning it takes the same amount of time to rotate on its axis as it does to orbit the Earth.
Explanation of the Assertion
- The Moon completes one full rotation on its axis approximately every 27.3 days.
- It also takes about 27.3 days to complete one orbit around the Earth.
- This synchronized motion is why we always see the same side of the Moon from Earth.
Evaluating the Reason
- The reason provided states that the Moon rotates about its own axis in 231/2 days.
- This duration is inaccurate; the correct period is approximately 27.3 days, not 231/2 days.
- Therefore, while the reason's concept is aligned with the assertion, the specifics are incorrect.
Conclusion
- The assertion is true as it correctly describes the Moon's synchronous rotation.
- The reason is false due to the incorrect duration of the Moon's rotation period.
Thus, the correct option is C: the assertion is true, but the reason is false. This distinction clarifies the relationship between the two statements, reinforcing the importance of accuracy in scientific explanations.
A person stood alone in a desert on a dark night and wanted to reach his village which was situated 5 km east of the point where he was standing. He had no instruments to find the direction but he located the polestar. The most convenient way now to reach his village is to walk in the- a)direction facing the polestar
- b)direction opposite to the polestar
- c)direction keeping the polestar to his left
- d)direction keeping the polestar to his right
Correct answer is option 'C'. Can you explain this answer?
A person stood alone in a desert on a dark night and wanted to reach his village which was situated 5 km east of the point where he was standing. He had no instruments to find the direction but he located the polestar. The most convenient way now to reach his village is to walk in the
a)
direction facing the polestar
b)
direction opposite to the polestar
c)
direction keeping the polestar to his left
d)
direction keeping the polestar to his right
|
Orion Classes answered |
In the Northern Hemisphere, the polestar, also known as Polaris, appears nearly fixed in the sky towards the north. As the person is standing in a desert and wants to reach a location 5 km east of his current position, he should keep the polestar to his left as he walks. This would ensure that he is heading roughly in an easterly direction, towards his village. Therefore, option (c) is the correct choice.
Which one of the following scholars suggests the earth’s origin is from gases and dust particles?- a)James Jeans
- b)H Alfven
- c)F Hoyle
- d)O Schmidit
Correct answer is option 'D'. Can you explain this answer?
Which one of the following scholars suggests the earth’s origin is from gases and dust particles?
a)
James Jeans
b)
H Alfven
c)
F Hoyle
d)
O Schmidit
|
|
Orion Classes answered |
Otto Schmidt, a Soviet scientist, was one of the scholars who suggested that the Earth's origin could be attributed to gases and dust particles. Schmidt proposed this theory as part of his research on the formation of celestial bodies, including planets like Earth. Therefore, option (d) is the correct choice.
If the stars are seen to rise perpendicular to the horizon by an observer, he is located on the- a)Equator
- b)Tropic of Cancer
- c)South Pole
- d)North Pole
Correct answer is option 'D'. Can you explain this answer?
If the stars are seen to rise perpendicular to the horizon by an observer, he is located on the
a)
Equator
b)
Tropic of Cancer
c)
South Pole
d)
North Pole
|
Grace Hughes answered |
Understanding Star Motion and Observer Location
When considering how stars appear to rise in the sky, the observer's geographical location plays a crucial role.
Location at the North Pole
- At the North Pole, which is located at 90 degrees North latitude, the celestial pole is directly overhead.
- Due to the Earth's rotation, stars appear to rise vertically from the horizon and set in the same manner.
- This phenomenon occurs because the observer is at the apex of the Earth's axis, making the stars seem to move in a circular path around the North Star, Polaris.
Comparison with Other Locations
- Equator: At the Equator, stars rise at an angle and set at an angle, moving almost directly east to west.
- Tropic of Cancer: Similar to the Equator, stars rise and set at an angle, but their path changes with the seasons due to the tilt of the Earth's axis.
- South Pole: At the South Pole, stars also appear to rise and set, but in a manner opposite to the North Pole, circling around the South Celestial Pole.
Conclusion
- Therefore, the unique observation of stars rising perpendicular to the horizon is exclusive to the North Pole, making it the correct answer.
- This distinctive view is a result of the observer's position at the Earth's axis, leading to a vertical rise of stars in the night sky.
When considering how stars appear to rise in the sky, the observer's geographical location plays a crucial role.
Location at the North Pole
- At the North Pole, which is located at 90 degrees North latitude, the celestial pole is directly overhead.
- Due to the Earth's rotation, stars appear to rise vertically from the horizon and set in the same manner.
- This phenomenon occurs because the observer is at the apex of the Earth's axis, making the stars seem to move in a circular path around the North Star, Polaris.
Comparison with Other Locations
- Equator: At the Equator, stars rise at an angle and set at an angle, moving almost directly east to west.
- Tropic of Cancer: Similar to the Equator, stars rise and set at an angle, but their path changes with the seasons due to the tilt of the Earth's axis.
- South Pole: At the South Pole, stars also appear to rise and set, but in a manner opposite to the North Pole, circling around the South Celestial Pole.
Conclusion
- Therefore, the unique observation of stars rising perpendicular to the horizon is exclusive to the North Pole, making it the correct answer.
- This distinctive view is a result of the observer's position at the Earth's axis, leading to a vertical rise of stars in the night sky.
Which one of the following planets has largest number of natural satellites or moons?- a)Jupiter
- b)Mars
- c)Saturn
- d)Venus
Correct answer is option 'C'. Can you explain this answer?
Which one of the following planets has largest number of natural satellites or moons?
a)
Jupiter
b)
Mars
c)
Saturn
d)
Venus
|
|
Orion Classes answered |
Saturn has the largest number of natural satellites or moons among the listed planets. It boasts an impressive count of over 80 confirmed moons, with more discoveries ongoing. These moons vary in size and characteristics, with some as large as planets themselves, like Titan, the second-largest moon in the solar system. The abundance of moons around Saturn makes it a fascinating celestial object for study, offering insights into planetary formation and the dynamics of moon systems.
Ganymede, the biggest moon in our solar system, belongs to which planet?- a)Saturn
- b)Uranus
- c)Neptune
- d)Jupiter
Correct answer is option 'D'. Can you explain this answer?
Ganymede, the biggest moon in our solar system, belongs to which planet?
a)
Saturn
b)
Uranus
c)
Neptune
d)
Jupiter
|
|
Orion Classes answered |
Ganymede, the largest moon in our solar system, orbits Jupiter. It is even larger than the planet Mercury. Ganymede is a fascinating world with its own magnetic field and a diverse surface featuring both heavily cratered regions and smooth plains. It is also thought to have a subsurface ocean beneath its icy crust, making it a target of interest for scientific exploration in the search for potential habitats for extraterrestrial life.
The planet(s) with no moons is/are- a)Venus and Mars
- b)Mars and Neptune
- c)Mercury and Mars
- d)Mercury and Venus
Correct answer is option 'D'. Can you explain this answer?
The planet(s) with no moons is/are
a)
Venus and Mars
b)
Mars and Neptune
c)
Mercury and Mars
d)
Mercury and Venus
|
|
Orion Classes answered |
The planet(s) in our solar system with no moons are Mercury and Venus. Mercury, the closest planet to the Sun, lacks any natural satellites orbiting around it. Venus, often referred to as Earth's sister planet due to its similar size and composition, also does not have any moons. While both planets have been extensively studied, their lack of moons sets them apart from other planets in the solar system, contributing to their unique characteristics and features.
The planet whose density is less than water and on keeping in the water it will start to float:- a)Mercury
- b)Saturn
- c)Venus
- d)Mars
Correct answer is option 'B'. Can you explain this answer?
The planet whose density is less than water and on keeping in the water it will start to float:
a)
Mercury
b)
Saturn
c)
Venus
d)
Mars
|
|
Orion Classes answered |
Saturn's density is less than that of water. Its average density is approximately 0.69 times the density of water, making it less dense than water. Therefore, if Saturn were placed in a body of water large enough to contain it, it would indeed float.
Which one of the following statements is correct with reference to our solar system?- a)The Earth is the densest of all the planets in our solar system
- b)The predominant element in the composition of Earth is silicon
- c)The Sun contains 75 percent of the mass of the solar system
- d)The diameter of the Sun is 190 times that of the Earth
Correct answer is option 'A'. Can you explain this answer?
Which one of the following statements is correct with reference to our solar system?
a)
The Earth is the densest of all the planets in our solar system
b)
The predominant element in the composition of Earth is silicon
c)
The Sun contains 75 percent of the mass of the solar system
d)
The diameter of the Sun is 190 times that of the Earth
|
|
Orion Classes answered |
The Earth is the densest planet in our solar system, primarily due to its composition, which includes heavy elements like iron and nickel in its core. This density contributes to its strong gravitational pull compared to other planets. Therefore, option (a) is the correct choice. Thank you for your patience.
What is the approximate mean velocity with which the Earth moves round the Sun in its orbit?- a)20km/s
- b)30km/s
- c)40km/s
- d)50km/s
Correct answer is option 'B'. Can you explain this answer?
What is the approximate mean velocity with which the Earth moves round the Sun in its orbit?
a)
20km/s
b)
30km/s
c)
40km/s
d)
50km/s
|
|
Orion Classes answered |
The approximate mean velocity with which the Earth moves around the Sun in its orbit is about:
(b) 30 km/s
This velocity can vary slightly depending on the Earth's position in its elliptical orbit, but on average, it's around 30 kilometers per second.
Among the following which planet takes maximum time for one revolution around the Sun?- a)Earth
- b)Jupiter
- c)Mars
- d)Venus
Correct answer is option 'B'. Can you explain this answer?
Among the following which planet takes maximum time for one revolution around the Sun?
a)
Earth
b)
Jupiter
c)
Mars
d)
Venus
|
|
Orion Classes answered |
Among the options provided, the planet that takes the maximum time for one revolution around the Sun is:
(b) Jupiter.
Jupiter has the longest orbital period of approximately 11.86 Earth years. This means it takes Jupiter about 11.86 Earth years to complete one full orbit around the Sun. This is longer than the orbital periods of Earth, Mars, and Venus. Therefore, Jupiter takes the maximum time for one revolution around the Sun among the listed options.
Halley’s comet completes one revolution around the sun in:- a)40 years
- b)46 years
- c)60 years
- d)76 years
Correct answer is option 'D'. Can you explain this answer?
Halley’s comet completes one revolution around the sun in:
a)
40 years
b)
46 years
c)
60 years
d)
76 years
|
|
Orion Classes answered |
Halley's Comet completes one revolution around the Sun in approximately (d) 76 years. This periodic comet is visible from Earth roughly every 75–76 years. It was last seen in 1986 and is predicted to return in 2061. Named after the astronomer Edmond Halley, who calculated its orbit in 1705, Halley's Comet is one of the most well-known and studied comets in history.
Who among the following proposed Laws of planetary motion?- a)Newton
- b)Kepler
- c)Ptolemy
- d)Copernicus
Correct answer is option 'B'. Can you explain this answer?
Who among the following proposed Laws of planetary motion?
a)
Newton
b)
Kepler
c)
Ptolemy
d)
Copernicus
|
|
Orion Classes answered |
Johannes Kepler proposed the Laws of Planetary Motion. In the early 17th century, based on meticulous observations by Tycho Brahe, Kepler formulated three fundamental laws describing the motion of planets around the Sun. Kepler's laws state that planets move in elliptical orbits with the Sun at one focus (First Law), the line joining a planet to the Sun sweeps out equal areas in equal times (Second Law), and the square of a planet's orbital period is proportional to the cube of the semi-major axis of its orbit (Third Law).
Who had proved first that our earth and another planet are revolving?- a)Aristotle
- b)Galileo
- c)Copernicus
- d)Edwin Hubble
Correct answer is option 'C'. Can you explain this answer?
Who had proved first that our earth and another planet are revolving?
a)
Aristotle
b)
Galileo
c)
Copernicus
d)
Edwin Hubble
|
|
Orion Classes answered |
The correct answer is (c) Copernicus. Nicolaus Copernicus, a Polish astronomer, proposed the heliocentric model of the solar system in the 16th century. He argued that the Earth and other planets revolve around the Sun, challenging the prevailing geocentric model where Earth was believed to be the center of the universe. Galileo Galilei provided observational evidence supporting Copernicus's heliocentric model through his telescopic observations in the 17th century, but Copernicus was the first to propose the idea.
Phobos and Deimos are the natural satellites of which planet?- a)Mars
- b)Mercury
- c)Neptune
- d)Uranus
Correct answer is option 'A'. Can you explain this answer?
Phobos and Deimos are the natural satellites of which planet?
a)
Mars
b)
Mercury
c)
Neptune
d)
Uranus
|
|
Orion Classes answered |
The natural satellites Phobos and Deimos are both moons of the planet Mars. They were discovered in 1877 by American astronomer Asaph Hall. Phobos is the larger and closer of the two moons to Mars, while Deimos is smaller and orbits further away. These moons are thought to be captured asteroids due to their irregular shapes and low densities compared to the rocky bodies found in the asteroid belt. They are named after the sons of the Greek god Ares, who is equivalent to the Roman god Mars.
A “Black Hole “is a body in space which does not allow any radiation to come out. This property is due to its- a)Very small size
- b)Very large size
- c)Very high density
- d)Very low density
Correct answer is option 'C'. Can you explain this answer?
A “Black Hole “is a body in space which does not allow any radiation to come out. This property is due to its
a)
Very small size
b)
Very large size
c)
Very high density
d)
Very low density
|
|
Orion Classes answered |
A black hole's property of not allowing any radiation to come out is due to its extremely high density. The gravitational pull of a black hole is so strong that not even light can escape from it, resulting in its characteristic feature of being "black" or devoid of any observable radiation. Therefore, option (c) is the correct choice.
What is the average distance (approximate) between the Sun & the Earth?- a)70 x 105 km
- b)100 x 105
- c)110 x 106 km
- d)150 x 106 km
Correct answer is option 'D'. Can you explain this answer?
What is the average distance (approximate) between the Sun & the Earth?
a)
70 x 105 km
b)
100 x 105
c)
110 x 106 km
d)
150 x 106 km
|
|
Orion Classes answered |
The average distance between the Sun and the Earth is approximately 150 x 106 kilometers, often referred to as one astronomical unit (AU). This distance serves as a fundamental unit for measuring distances within the solar system. Understanding this distance is crucial for studying celestial mechanics, planetary orbits, and astronomical phenomena. It's the baseline for calculating distances to other planets, asteroids, and celestial bodies, forming a key reference point in astronomical observations and calculations.
Geo centric model of solar system was proposed by:- a)Copernicus
- b)Ptolemy
- c)Aristotle
- d)Strabo
Correct answer is option 'B'. Can you explain this answer?
Geo centric model of solar system was proposed by:
a)
Copernicus
b)
Ptolemy
c)
Aristotle
d)
Strabo
|
|
Orion Classes answered |
The geocentric model of the solar system was proposed by (b) Ptolemy. Ptolemy was an ancient Greek astronomer who lived in the 2nd century AD. He developed a comprehensive cosmological model known as the Ptolemaic system, which placed the Earth at the center of the universe with all celestial bodies, including the Sun, Moon, planets, and stars, orbiting around it. This geocentric model was widely accepted for centuries until it was replaced by the heliocentric model proposed by Copernicus in the 16th century.
On 21st June, the Sun- a)Does not set below the horizon at the Arctic Circle
- b)Does not set below the horizon at Antarctic Circle
- c)Shines vertically overhead at noon on the Equator
- d)Shines vertically overhead at the Tropic of Capricorn
Correct answer is option 'A'. Can you explain this answer?
On 21st June, the Sun
a)
Does not set below the horizon at the Arctic Circle
b)
Does not set below the horizon at Antarctic Circle
c)
Shines vertically overhead at noon on the Equator
d)
Shines vertically overhead at the Tropic of Capricorn
|
|
Orion Classes answered |
On 21st June, the summer solstice in the Northern Hemisphere, the Sun does not set below the horizon at the Arctic Circle. This phenomenon is known as the "midnight sun," where areas north of the Arctic Circle experience continuous daylight for 24 hours. Conversely, during the same period, the Antarctic Circle experiences the polar night, with the Sun not rising above the horizon. This occurrence marks the tilt of the Earth's axis towards the Sun, resulting in longer daylight hours in the Northern Hemisphere and shorter daylight hours in the Southern Hemisphere.
One Astronomical Unit is the average distance between- a)Earth and the Sun
- b)Earth and the Moon
- c)Jupiter and the Sun
- d)Pluto and the Sun
Correct answer is option 'A'. Can you explain this answer?
One Astronomical Unit is the average distance between
a)
Earth and the Sun
b)
Earth and the Moon
c)
Jupiter and the Sun
d)
Pluto and the Sun
|
|
Orion Classes answered |
One Astronomical Unit (AU) is a unit of measurement used in astronomy to represent the average distance between the Earth and the Sun. It's a convenient way to describe distances within our solar system.
So, the correct answer is indeed:
(a) Earth and the Sun
Who among the following proposed Helio-centric model of solar system?- a)Copernicus
- b)Ptolemy
- c)Aristotle
- d)Strabo
Correct answer is option 'A'. Can you explain this answer?
Who among the following proposed Helio-centric model of solar system?
a)
Copernicus
b)
Ptolemy
c)
Aristotle
d)
Strabo
|
|
Orion Classes answered |
The correct answer is (a) Copernicus. Nicolaus Copernicus, a Polish astronomer, proposed the heliocentric model of the solar system in the 16th century. He argued that the Sun, not the Earth, was the center of the solar system, and that the planets, including Earth, revolve around the Sun. This model replaced the geocentric model proposed by Ptolemy and became a foundational concept in modern astronomy.
What is the difference between asteroids and comets? - Asteroids are small rocky planetoids, while comets are formed of frozen gases held together by rocky and metallic material
- Asteroids are found mostly between the orbits of Jupiter and Mars, while comets are found mostly between Venus & Mercury
- Comets show a perceptible glowing tail, while asteroids do not
Which of the statements given above is/are correct?- a)1 and 2 only
- b)1 and 3 only
- c)3 only
- d)1,2 and 3 only
Correct answer is option 'B'. Can you explain this answer?
What is the difference between asteroids and comets?
- Asteroids are small rocky planetoids, while comets are formed of frozen gases held together by rocky and metallic material
- Asteroids are found mostly between the orbits of Jupiter and Mars, while comets are found mostly between Venus & Mercury
- Comets show a perceptible glowing tail, while asteroids do not
Which of the statements given above is/are correct?
a)
1 and 2 only
b)
1 and 3 only
c)
3 only
d)
1,2 and 3 only
|
|
Orion Classes answered |
Asteroids are indeed small rocky planetoids, while comets are formed of frozen gases held together by rocky and metallic material.
Comets show a perceptible glowing tail due to the sublimation of volatile materials when they approach the Sun, while asteroids typically do not exhibit such tails.
Statement 2 is incorrect. Asteroids are found mostly between the orbits of Mars and Jupiter in a region called the asteroid belt, while comets are generally found further out in the solar system, though they can appear anywhere in the sky when they enter the inner solar system.
Comets show a perceptible glowing tail due to the sublimation of volatile materials when they approach the Sun, while asteroids typically do not exhibit such tails.
Statement 2 is incorrect. Asteroids are found mostly between the orbits of Mars and Jupiter in a region called the asteroid belt, while comets are generally found further out in the solar system, though they can appear anywhere in the sky when they enter the inner solar system.
Who speculated that our universe is expanding?- a)Newton
- b)Edwin Hubble
- c)Galilio
- d)Copernicus
Correct answer is option 'B'. Can you explain this answer?
Who speculated that our universe is expanding?
a)
Newton
b)
Edwin Hubble
c)
Galilio
d)
Copernicus
|
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Orion Classes answered |
The individual who first speculated that our universe is expanding is Edwin Hubble. So, the correct answer is (b) Edwin Hubble. Edwin Hubble, an American astronomer, made observations in the 1920s that showed galaxies were moving away from each other, implying that the universe is expanding. This discovery fundamentally changed our understanding of the cosmos and led to the development of the Big Bang theory, which proposes that the universe began from an extremely hot and dense state and has been expanding ever since.
In order of their distances from the Sun, which of the following planets lie between Mars & Uranus?- a)Earth and Jupiter
- b)Jupiter and Saturn
- c)Saturn and Earth
- d)Saturn and Neptune
Correct answer is option 'B'. Can you explain this answer?
In order of their distances from the Sun, which of the following planets lie between Mars & Uranus?
a)
Earth and Jupiter
b)
Jupiter and Saturn
c)
Saturn and Earth
d)
Saturn and Neptune
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Orion Classes answered |
To determine which planets lie between Mars and Uranus in order of their distances from the Sun, let's list the planets in their correct order:
- Mercury
- Venus
- Earth
- Mars
- Jupiter
- Saturn
- Uranus
- Neptune
From this list, the planets that lie between Mars and Uranus are Jupiter and Saturn. Therefore, the correct answer is option (b) Jupiter and Saturn.
Which one of the following planet is also called morning star or evening star?- a)Mercury
- b)Venus
- c)Mars
- d)Saturn
Correct answer is option 'B'. Can you explain this answer?
Which one of the following planet is also called morning star or evening star?
a)
Mercury
b)
Venus
c)
Mars
d)
Saturn
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Orion Classes answered |
Venus, the second planet from the Sun, is often referred to as the "morning star" or "evening star" due to its brightness and visibility in the sky. Depending on its position relative to Earth, Venus can be seen either in the eastern sky before sunrise, where it is called the morning star, or in the western sky after sunset, where it is called the evening star. This dual appearance has fascinated skywatchers throughout history and has earned Venus its celestial nicknames.
Which is the nearest of the sun?- a)Beta centaury
- b)Alpha centaury
- c)Gamma centaury
- d)Proxima centaury
Correct answer is option 'D'. Can you explain this answer?
Which is the nearest of the sun?
a)
Beta centaury
b)
Alpha centaury
c)
Gamma centaury
d)
Proxima centaury
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Orion Classes answered |
Proxima Centauri is the nearest star to the Sun. It is part of the Alpha Centauri star system, located about 4.24 light-years away from Earth in the constellation of Centaurus. Proxima Centauri is a red dwarf star, much smaller and cooler than the Sun, making it faint and challenging to observe with the naked eye. Despite its proximity, Proxima Centauri is still quite distant on astronomical scales, but it holds significance for astronomers studying exoplanets and potential habitability in its vicinity.
Sun’s halo is produced by the refraction of light in- a)Water vapour in Stratus clouds
- b)Ice crystals in Cirro-Cumulus clouds
- c)Ice crystals in Cirrus clouds
- d)Dust particles in Stratus clouds
Correct answer is option 'C'. Can you explain this answer?
Sun’s halo is produced by the refraction of light in
a)
Water vapour in Stratus clouds
b)
Ice crystals in Cirro-Cumulus clouds
c)
Ice crystals in Cirrus clouds
d)
Dust particles in Stratus clouds
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Orion Classes answered |
The halo around the Sun is produced by the refraction of light through ice crystals in the atmosphere. Among the options provided, the correct one is:
(c) Ice crystals in Cirrus clouds
Cirrus clouds are thin, wispy clouds found at high altitudes, typically composed of ice crystals. These ice crystals can refract sunlight and create optical phenomena such as halos around the Sun.
The device employed to measure the diameters of stars and our galaxy (Milky Way) is called:- a)Photometer
- b)Barometer
- c)Viscometer
- d)Interferometer
Correct answer is option 'D'. Can you explain this answer?
The device employed to measure the diameters of stars and our galaxy (Milky Way) is called:
a)
Photometer
b)
Barometer
c)
Viscometer
d)
Interferometer
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Orion Classes answered |
The device employed to measure the diameters of stars and our galaxy (Milky Way) is called an interferometer. So, the correct answer is (d) Interferometer. Interferometry is a technique that utilizes the interference of waves to make precise measurements of distances or sizes, particularly in astronomy. By combining the light from different telescopes or using multiple paths of light, interferometers can achieve very high resolution, allowing astronomers to measure the diameters of distant stars and galaxies.
Chapter doubts & questions for Astronomy - Science for ACT 2025 is part of ACT exam preparation. The chapters have been prepared according to the ACT exam syllabus. The Chapter doubts & questions, notes, tests & MCQs are made for ACT 2025 Exam. Find important definitions, questions, notes, meanings, examples, exercises, MCQs and online tests here.
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