pls check my answers.
1. What shape is the moon's orbit around Earth?
a circle
an ellipse that is almost circular (my answer)
a spiral
an ellipse that is elongated
2. Which did Kepler notice FIRST about planetary motion that caused him to propose Kepler’s first law of orbital motion?
The planets have circular orbits.
The distance between Mars and the sun is constant.
The planets speed up and slow down but cover the same area.
Most planets have highly elliptical orbits. (my answer)
3. For which project would knowledge of Kepler's laws prove most useful?
determining the structure of the solar system's planets
putting a communications satellite in Earth orbit (my answer)
calculating the mass of Earth
measuring the distance between Earth and the moon
4. A line between a planet and the sun sweeps out two equal areas at different places as it moves along its orbit. Which factor remains constant as this happens?
the time the planet takes to sweep out the areas (my answer)
the distance from the sun to the planet while it sweeps out the areas
the planet’s speed as it sweeps out the areas
the energy required to sweep out the areas
5. A highly eccentric orbit, such as a comet, will have an eccentricity of 0.
True
False (my answer)
6. Which was a belief of Copernicus's model of the solar system?
The planets move in perfect circles. (my answer)
All planets orbit the Sun at the same speed.
The outer planets move in epicycles.
Earth is fixed to a crystalline sphere.
7. Which statement about the geocentric model is true?
It shows the orbits of the planets as elliptical.
It shows Earth at the center of the solar system. (my answer)
It shows the Sun at the center of the solar system.
8. Which of the following statements about Newton's theory of universal gravitation is true?
Gravitational force increases as the distance between objects increases. (my answer)
Gravitational force increases as mass of objects decreases.
Gravitational force increases as the mass of objects increases.
The theory applies only to objects on Earth.
9. An asteroid approaches Jupiter and is slung into a new trajectory around across the solar system. If it's eccentricity is greater than 1, which statement might be true?
The asteroid slows down as it passes around Jupiter.
The asteroid continues out of the solar system, never to return. (my answer)
The asteroid adopts an unusual orbit around the sun, such as an egg shape.
The asteroid falls into an regular orbit around Jupiter instead of the sun.
10. The mass of an object doubles. What happens to the gravitational force between it and another object, assuming they remain the same distance apart?
The amount of the gravitational force decreases by one-half.
The amount of the gravitational force quadruples.
The amount of the gravitational force doubles. (my answer)
The amount of the gravitational force remains the same.
11. Based on Kepler's observations about planetary motion, what is the relationship between a planet's orbital velocity and its distance from the sun?
The greater the distance, the slower the orbital velocity. (my answer)
Distance has no effect on orbital velocity.
The greater the distance, the greater the orbital velocity.
As distance is cut in half, orbital velocity decreases.
12. Why was the geocentric model accepted for more than a thousand years?
It correctly explained the motion of the planets. (my answer)
It correctly described the solar system.
It was confirmed by astronomers using telescopes.
It correctly explained the distribution of the stars.
13. Select the correct answer to complete the sentence. Gravitational force is said to be universal because:
it operates in one direction.
it operates only within our solar system.
it applies mainly to planets and moons.
it applies to all objects. (my answer)
14. Select the correct words to fill in the blanks to this sentence: As a planet draws away from the sun in its orbit, the gravity pull from the sun pulls _________on the planet and the planet's speed _________.
forwards, decreases
backwards, decreases (my answer)
backwards, increases
forwards, increases
15. Why is it important that Earth’s orbit is nearly circular?
This prevents massive temperature fluctuations that could occur with a more extremely elliptical orbit. (my answer)
This allows for massive temperature fluctuations that occur with a more circular orbit.
This prevents massive temperature fluctuations that could occur with a more circular orbit.
This allows for gravitational fluctuations that occur with a more extremely elliptical orbit.
16. As the MASS of an object increases, its gravitational force ___________.
decreases
increases (my answer)
stays the same
17. Why were Tycho Brahe's data and observations important for Kepler's laws?
They proved one of the laws to be true. (my answer)
They disproved the laws.
They provided evidence to support the laws.
They had no relation to the laws.
18. The acceleration of a satellite can be derived by equating the universal gravitational force and the centripetal force.
True (my answer)
False
19. Which is the LEAST eccentric orbit?
e=0.001 (my answer)
e=0.90
e=1
e=0.25
20. There are two objects close to each other. If the mass of one of the objects is doubled while the distance remains the same, how does the gravitational force change?
It becomes four times stronger
It becomes half as strong
It remains the same
It becomes twice as strong (my answer)
21. Which two things affect gravitational force between objects?
Mass and distance (my answer)
Mass and cellular composition
Mass and shape
Distance and shape
22. Which of the eight planets in the solar system has the most elliptical orbit?
Venus
Earth
Mars
Mercury (my answer)
23. Where is the sun located on Earth’s elliptical orbit?
at the aphelium
at the perihelium
at a focus (my answer)
at the center of the two foci
24. According to Newton’s Laws of Motion objects will continue in a straight line at a constant _________ unless acted on by an outside _____________.
location, planet
speed, force (my answer)
speed, time
location, force
Your answers are mostly correct. However, here is the correction for one question:
Question 19:
The correct answer is e=0.001 (your answer is correct)
1. Correct. The moon's orbit around Earth is an ellipse that is almost circular.
2. Correct. Kepler noticed that the planets speed up and slow down but cover the same area, which led him to propose Kepler's first law of orbital motion.
3. Correct. Knowledge of Kepler's laws would be most useful for putting a communications satellite in Earth's orbit.
4. Correct. The time the planet takes to sweep out the areas remains constant as the line between the planet and the sun sweeps out two equal areas at different places.
5. Incorrect. A highly eccentric orbit, such as a comet, will have an eccentricity greater than 0.
6. Correct. Copernicus believed that the planets move in perfect circles in his model of the solar system.
7. Correct. The geocentric model shows Earth at the center of the solar system.
8. Incorrect. Gravitational force increases as the mass of objects increases according to Newton's theory of universal gravitation.
9. Incorrect. If the eccentricity of an orbit is greater than 1, it is not a closed elliptical orbit. The asteroid could adopt an unusual orbit around the sun or fall into a regular orbit around Jupiter instead of the sun, but it would not continue out of the solar system.
10. Incorrect. When the mass of an object doubles, the gravitational force between the objects also doubles according to Newton's law of universal gravitation.
11. Correct. Based on Kepler's observations, the greater the distance between a planet and the sun, the slower the orbital velocity.
12. Correct. The geocentric model was accepted for more than a thousand years because it correctly explained the motion of the planets.
13. Correct. Gravitational force is said to be universal because it applies to all objects, not just within our solar system.
14. Incorrect. As a planet draws away from the sun in its orbit, the gravity pull from the sun pulls forwards on the planet and the planet's speed increases.
15. Correct. It is important that Earth's orbit is nearly circular because it helps prevent massive temperature fluctuations that could occur with a more extremely elliptical orbit.
16. Correct. As the mass of an object increases, its gravitational force also increases.
17. Correct. Tycho Brahe's data and observations provided evidence to support Kepler's laws.
18. Correct. The acceleration of a satellite can be derived by equating the universal gravitational force and the centripetal force.
19. Correct. An orbit with e=0.001 is the least eccentric orbit.
20. Correct. If the mass of one of the objects is doubled while the distance remains the same, the gravitational force between the objects becomes twice as strong.
21. Correct. Mass and distance are the two factors that affect gravitational force between objects.
22. Correct. Mercury has the most elliptical orbit among the eight planets in the solar system.
23. Correct. The sun is located at a focus of Earth’s elliptical orbit.
24. Correct. According to Newton’s Laws of Motion, objects will continue in a straight line at a constant speed unless acted on by an outside force.
Based on your provided answers, here is the feedback for each question:
1. What shape is the moon's orbit around Earth? - Correct, the moon's orbit around Earth is an ellipse that is almost circular.
2. Which did Kepler notice FIRST about planetary motion that caused him to propose Kepler’s first law of orbital motion? - Correct, Kepler noticed that most planets have highly elliptical orbits, which led him to propose his first law.
3. For which project would knowledge of Kepler's laws prove most useful? - Incorrect, knowledge of Kepler's laws would be most useful for determining the structure of the solar system's planets, not putting a communications satellite in Earth orbit.
4. A line between a planet and the sun sweeps out two equal areas at different places as it moves along its orbit. Which factor remains constant as this happens? - Correct, the time the planet takes to sweep out the areas remains constant.
5. A highly eccentric orbit, such as a comet, will have an eccentricity of 0. - Incorrect, a highly eccentric orbit will have an eccentricity greater than 0, so the correct answer is False.
6. Which was a belief of Copernicus's model of the solar system? - Correct, Copernicus believed that the planets move in perfect circles.
7. Which statement about the geocentric model is true? - Correct, the geocentric model shows Earth at the center of the solar system.
8. Which of the following statements about Newton's theory of universal gravitation is true? - Incorrect, gravitational force increases as the mass of objects increases, not as the distance between objects increases.
9. An asteroid approaches Jupiter and is slung into a new trajectory across the solar system. If its eccentricity is greater than 1, which statement might be true? - Correct, if the eccentricity is greater than 1, it is possible that the asteroid continues out of the solar system, never to return.
10. The mass of an object doubles. What happens to the gravitational force between it and another object, assuming they remain the same distance apart? - Correct, the gravitational force doubles when the mass of an object doubles.
11. Based on Kepler's observations about planetary motion, what is the relationship between a planet's orbital velocity and its distance from the sun? - Correct, the greater the distance, the slower the orbital velocity.
12. Why was the geocentric model accepted for more than a thousand years? - Incorrect, the geocentric model was accepted for more than a thousand years because it was the most widely believed and supported model at that time.
13. Select the correct answer to complete the sentence. Gravitational force is said to be universal because: - Correct, gravitational force applies to all objects.
14. Select the correct words to fill in the blanks to this sentence: As a planet draws away from the sun in its orbit, the gravity pull from the sun pulls backwards on the planet and the planet's speed decreases.
15. Why is it important that Earth’s orbit is nearly circular? - Correct, a nearly circular orbit prevents massive temperature fluctuations that could occur with a more extremely elliptical orbit.
16. As the mass of an object increases, its gravitational force increases.
17. Why were Tycho Brahe's data and observations important for Kepler's laws? - Correct, Tycho Brahe's data and observations provided evidence to support Kepler's laws.
18. The acceleration of a satellite can be derived by equating the universal gravitational force and the centripetal force. - Correct, this statement is true.
19. Which is the LEAST eccentric orbit? - Correct, an eccentricity of 0.001 indicates the least eccentric orbit.
20. There are two objects close to each other. If the mass of one of the objects is doubled while the distance remains the same, the gravitational force between them becomes twice as strong.
21. Which two things affect gravitational force between objects? - Correct, mass and distance affect gravitational force between objects.
22. Which of the eight planets in the solar system has the most elliptical orbit? - Incorrect, Mars has the most elliptical orbit among the eight planets in the solar system.
23. Where is the sun located on Earth’s elliptical orbit? - Correct, the sun is located at a focus of Earth's elliptical orbit.
24. According to Newton’s Laws of Motion, objects will continue in a straight line at a constant speed unless acted on by an outside force.