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