Chapter 10 - Projectile and Satellite Motion

The conservation of energy applies to satellites in

• elliptical orbits

• circular orbits

• both

Project a cannonball from atop Newton's hypothetical mountain at 8 km/s and it orbits Earth. Project it at 9 km/s and the shape of the orbit is

• an ellipse

• a circle

• a wide parabola

A dropped ball gains speed because

• a gravitational force acts on it

• inertia

• its velocity changes

• its nature is to become closer to the Earth

A lunar month is about 28 days. If the Moon were closer to Earth than it is now, the lunar month would be

• less than 28 days

• more than 28 days

• about 28 days

Communications and weather satellites always appear at the same place in the sky, because these satellites are

• stationary in space

• orbiting Earth with a 24 hour period

• beyond the pull of the Earth's gravitational field

• moving at a speed just short of escape velocity

According to Kepler, the speed of a planet is slowest when it is

• farthest from the Sun

• neither, for speed is constant

• closest to the sun

An astronaut at Earth's surface has a mass of 50 kg and a weight of 500 N. If she were floating freely inside a space habitat in remote space, she would have

• more weight and no mass

• no weight and less mass

• no weight and the same mass

• none of the above

Which of these vary for satellites in circular orbits?

• kinetic energy

• speed

• momentum

• none of the above

Escape speed from the Moon is

• about the same as from Earth

• much greater than from Earth

• much less than from Earth

The tangential velocity of an Earth satellite is its velocity

• parallel to the surface of the Earth

• attributed to satellites moving in any direction

• perpendicular to the surface of Earth