Sci 8 Earth's Motion HW #2

What are the factors which combine to to keep celestial bodies in orbit? 

• Air Resistance and Gravity 
• Gravity and Inertia 
• Inertia and orbital speed
• Orbital speed and gravity 

The strength of the force of gravity depends on:

• the masses of the objects and their speeds.
• the masses of the objects and the distance between them.
• the weight of the objects and their speeds.
• the masses of the objects and their weights.

According to Kepler’s discoveries, planets orbit around the Sun:

• in an oval shape.
• in perfect circles.
• in an ellipse.
• in a rectangular shape.

As mass increases, gravity ________________.

• Increases 
• Decreases 
• Stays the same 

As mass decreases, gravity ______________________.

• Increases 
• Decreases 
• Stays the same 

As distance increases, gravity __________________.

• Increases 
• Decreases 
• Stays the same 

As distance decreases, gravity ___________________.

• Increases 
• Decreases 
• Stays the same 

The orbital path of a satellite is shown in the sketch. Use the sketch to answer the question.

In which of the positions A through D does the satellite have the most KE?

• A

• B

• C

• D

The orbital path of a satellite is shown in the sketch. Use the sketch to answer the question.

At what point does the satellite have most PE?

• A

• B

• C

• D

What are the two center points of an ellipse called?

• Orbits

• Foci

• Midpoints

• Major axis