Which did Kepler notice about planetary motion that caused him to propose Kepler’s first law of orbital motion?(1 point)
Responses
The distance between Mars and the sun is constant.
The distance between Mars and the sun is constant.
The planets have circular orbits.
The planets have circular orbits.
The distance to the sun varies.
The distance to the sun varies.
Most planets have highly elliptical orbits.
The planets have highly elliptical orbits.
For a moon orbiting its planet, rp
is the shortest distance between the moon and its planet and ra
is the longest distance between the moon and its planet. What is a moon's orbital eccentricity if rp
is equal to 0.27ra
?(1 point)
Responses
0.48
0.48
0.27
0.27
0.57
0.57
0.65
0.65
0.65
Which of the following statements about Newton's theory of universal gravitation are true? Select the three correct answers.(2 points)
Responses
Gravitational force increases as the distance between objects decreases.
Gravitational force increases as the distance between objects decreases.
The theory applies only to objects on Earth.
The theory applies only to objects on Earth.
Gravitational force increases as the mass of objects increases.
Gravitational force increases as the mass of objects increases.
Gravitational force increases as mass of objects decreases.
Gravitational force increases as mass of objects decreases.
The theory applies to all objects in the universe.
The theory applies to all objects in the universe.
Gravitational force increases as the distance between objects increases.
Gravitational force increases as the distance between objects decreases.
Gravitational force increases as the mass of objects increases.
The theory applies to all objects in the universe.
The mass of an object doubles. What happens to the gravitational force between it and another object whose mass stays the same, assuming they remain the same distance apart?(1 point)
Responses
The amount of the gravitational force quadruples.
The amount of the gravitational force quadruples.
The amount of the gravitational force doubles.
The amount of the gravitational force doubles.
The amount of the gravitational force remains the same.
The amount of the gravitational force remains the same.
The amount of the gravitational force decreases by one-half.
The amount of the gravitational force doubles.
based on Kepler's observations about planetary motion, what is the relationship between a planet's orbital velocity and its distance from the sun?(1 point)
Responses
The greater the distance, the greater the orbital velocity.
The greater the distance, the greater the orbital velocity.
Distance has no effect on orbital velocity.
Distance has no effect on orbital velocity.
As distance is cut in half, orbital velocity decreases.
As distance is cut in half, orbital velocity decreases.
The greater the distance, the slower the orbital velocity.