Ch 9 Quiz Practice
Non zero, directed toward the spaceship
A hollow spherical planet is inhabited by people who live inside it, where the gravitational field is zero. When a very massive spaceship lands on the planet's surface, inhabitants find that the gravitational field inside the planet is
Both forces are the same
A very massive object A and a less massive object B move toward each other under the influence of gravity. Which force, if either, is greater?
100 N
A weight watcher who normally weighs 400 N stands on top of a very tall ladder so she is one Earth radius above Earth's surface. How much is her weight there?
40 N
An asteroid exerts a 360-N gravitational force on a nearby spacecraft. If the spacecraft moves to a position three times as far from the center of the asteroid, the force will be
Increases
As two objects moving toward each other due to gravity get closer, the acceleration of each
Extra high
During an eclipse of the Sun the high ocean tides on Earth are
Parts of the body would have to be appreciably closer to the Moon than other parts
For lunar tides to occur in the human body
Decrease to half
If Earth's mass decreased to one-half its original mass with no change in radius, then your weight would
Earth
If an object is placed exactly halfway between Earth and the Moon, it would fall toward the
2 tidal bulges
If the Moon were covered with water, tidal effects caused by Earth would find the Moon with
Not change.
If the Sun became twice as massive, your attraction to the Sun would double and your weight as measured on Earth would
The same
If the Sun collapsed to a black hole, Earth's gravitational attraction to it would be
Increase also
If the mass of Earth somehow increased with no change in radius, your weight would
The pull of Earth on the Sun would double, it's pull on Earth would double. Both of these
If the sun were twice as massive
Weight is zero
Inside a freely-falling runaway elevator, your
That gravity is universal
Newton discovered
Different times
On each given day and location, tides rise and fall at
Without support forces
Passengers in a high-flying jumbo jet feel their normal weight in flight, while passengers in an orbiting space vehicle do not, because passengers in the space vehicle are
The gravitational attraction to other planets
Planets wobble in their orbits due to
Winter
The Earth is closer to the Sun in January than in July, which accounts for the fact that the highest high tides in the Northern Hemisphere occur in
New of full moon
The best time for digging clams (when the low tide is extra low) is during the time of the
Newton's theory of gravitation
The concept of force is fundamental to
In the same direction as gravitational attraction
The direction of a gravitational field is
Four times greater
The force of Earth's gravity on a capsule in space increases as it comes closer. When the capsule moves to half its distance, the force toward Earth is then
Unknown at this time, subjects of intense astronomical interest Both of these
The identities of dark energy and dark matter are
On water closer to it than on water farther away
The main reason ocean tides exist is that Moon's pull is stronger
Jupiters radius is about 10 times earths radius
The planet Jupiter is about 300 times as massive as Earth, yet on its surface you would weigh only about 3 times as much because
After Newton's time
The universal gravitational constant G was first measured
Unequal forces acting on different parts of a body
Tidal forces in general are the result of
Oceans, interior, atmosphere All of the above
Tides caused mainly by the Moon occur in Earth's
In an accelerating elevator away from Earth, standing on Earth's surface, in a rotating habitat in space. All of the above
You can experience weight
In a freely falling elevator, momentarily when you step off a chair, in the absence of a supporting surface All of the above
You experience weightlessness