Physics Gravity and Gravitation 2

Question 1

Kepler's Second Law (Law of Equal Areas) states that a planet:

Accepted Answer

Sweeps out equal areas in equal time intervals as it orbits

Answer

Moves faster when farther from the Sun

Answer

Has an orbital period proportional to its distance from the Sun

Answer

Orbits the Sun in a perfect circle

Question 2

Kepler's Third Law states that the square of a planet's orbital period is proportional to:

Accepted Answer

The cube of its semi-major axis

Answer

Its orbital radius

Answer

The inverse square of its orbital radius

Answer

The square of its orbital eccentricity

Question 3

Escape velocity is defined as the minimum speed needed to:

Accepted Answer

Break free from a planet's gravitational field without further propulsion

Answer

Achieve a stable circular orbit around a planet

Answer

Travel from one planet to another in the solar system

Answer

Maintain a stable elliptical orbit

Question 4

Earth's escape velocity is approximately:

Accepted Answer

11.2 km/s

Answer

7.9 km/s

Answer

9.8 km/s

Answer

3.0 km/s

Question 5

In free fall, objects of different masses (ignoring air resistance):

Accepted Answer

All accelerate at the same rate g

Answer

Fall at rates proportional to their mass

Answer

Lighter objects fall faster

Answer

Fall at rates proportional to their weight

Question 6

A satellite in low Earth orbit completes one orbit in approximately:

Accepted Answer

90 minutes

Answer

24 hours

Answer

12 hours

Answer

6 hours

Question 7

The gravitational field strength g at a height h above Earth's surface is:

Accepted Answer

Less than at the surface

Answer

Greater than at the surface

Answer

Equal to the surface value regardless of height

Answer

Zero everywhere above the atmosphere