Q.1
What unit to we usually use to to measure a planet's orbital period?
  • year
  • astronomical unit
Q.2
What causes Earth’s year to be shorter than Jupiter’s year?
  • the shape of Earth’s orbit around the Sun
  • the mass and density of Jupiter
  • the distance between Earth and the Sun
  • What causes Earth’s year to be shorter than Jupiter’s year?
Q.3
What effect does increasing the distance between an ellipse’s foci have on the shape of an ellipse?
  • Increases eccentricity
  • no effect
Q.4
How can the position of the sun in earth's orbit be described?
  • The sun is at one of the two focal points of a slightly eccentric ellipse
  • The sun is at one of the two focal points of a highly eccentric ellipse
Q.5
Where will an object move at the greatest speed as it orbits the sun?
  • Aphelion
  • Between perihelion and aphelion
  • Perihelion
  • None of these
Q.6
What did Kepler discover about planets and their orbital speed?
  • Planets with the greatest mass will orbit the Sun with the fastest orbital speed.
  • Planets furthest from the Sun will orbit with the fastest orbital speed.
  • Planets closest to the Sun will orbit with the fastest orbital speed.
  • Planets with the least mass will orbit the Sun with the fastest orbital speed.
Q.7
Double the distance between two objects
  • 4 times greater gravity attraction
  • 2 times weaker gravity
  • 4 times weaker gravity attraction
  • 2 times greater gravity
Q.8
Double the product of the masses of two objects
  • 4 times weaker gravity force
  • 2 times weaker gravity force
  • 4 times stronger gravity force
  • 2 times stronger gravity force
Q.9
Which of the following can decrease the gravity between objects?
  • Remove mass
  • Decrease distance
0 h : 0 m : 1 s