physics chapter 9
If the mass of Earth somehow increased with no change in radius, your weight would
increase also
Which is most responsible for Earth's ocean tides?
the Moon
The best time for digging clams (when the low tide is extra low) is during the time of the
new or full moon
The force of Earth's gravity on a capsule in space will lessen as it moves farther away. If the capsule moves to twice its distance, the force toward Earth becomes
one-fourth as much as before
Half-way to the center of a planet of uniform density, your weight compared to that at the surface would be
one-half as much
For lunar tides to occur in the human body,
parts of the body would have to be appreciably closer to the Moon than other parts
Suppose the Moon had twice the diameter but the same mass and same orbital distance from Earth. In that case, the high tides on Earth would be
practically the same
The force of gravity acts on all apples on an apple tree. Some apples are twice as far from the ground as others. For the same mass, these twice-as-high apples have
practically the same weight.
If your mass, the mass of Earth, and the mass of everything in the solar system were twice as much as it is now, yet everything stayed the same size, your weight on Earth would
quadruple
An asteroid exerts a 360-N gravitational force on a nearby spacecraft. The 360-N force on the spacecraft is directed
toward the asteroid
Which rocket would require more fuel?
one going from Earth to the Moon
You can experience the feeling of weight
all of the above ( in an accelerating elevator away from Earth, standing on Earth's surface, in a rotating habitat in space)
You experience "weightlessness"
all of the above (momentarily when you step off a chair, in a freely falling elevator, in the absence of a supporting surface)
When the distance between two interacting objects doubles, the gravitational force is
1/4 as much as before
A weight watcher who normally weighs 400 N stands on top of a very tall ladder so that she is one Earth radius above Earth's surface. How much is her weight there?
100 N
If the Moon were covered with water, tidal effects caused by the Earth would cause the Moon to have
2 tidal bulges
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
40 N
What is the force of gravity on a 500-N woman standing on Earth's surface?
500 N
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
Jupiter's radius is about 10 times Earth's radius
Rate this statement: No force due to Earth's gravity acts on astronauts inside the orbiting space station
always false
Rate this statement: No force due to Earth's gravity acts on astronauts inside the orbiting space station.
always false
Earth's gravitational field extends
both inside and outside Earth and throughout the entire universe
If the Sun were twice as massive,
both of the above (the pull of Earth on the sun would double; its pull on Earth would double)
if the sun were twice as massive
both of the above (the pull of earth on the sun would double and its pull on earth would double)
To make a profit, a buyer purchases metal by weight at one altitude and sells it at the same price per pound at another altitude. The supplier should
buy at a high altitude and sell at a low altitude
If Earth's radius somehow increased with no change in mass, your weight would
decrease
If the Earth's mass decreased to one-half its original mass with no change in radius, then your weight would
decrease to half.
On each given day and location, tides rise and fall at
different times
The origin of any microtides in the human body is most likely the
earth
During an eclipse of the Sun, the high ocean tides on Earth are
extra high
How far must one travel to escape Earth's gravitational field?
forget it; you can't travel far enough
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
four times greater
The greater the masses of interacting objects, the
greater the gravitational force between them
The direction of a gravitational field is
in the same direction as gravitational attraction.
As two objects moving toward each other due to gravity get closer, the acceleration of each
increases
Two objects move toward each other due to gravity. As the objects get closer and closer, the force between them
increases
When the distance between two stars decreases to one-third of the initial distance, the force between them
increases to nine times as much.
If the Moon had twice as much mass and still orbited Earth at the same distance, ocean bulges on Earth would be
larger
If the Moon were four times as massive but twice as far from Earth, high tides on Earth would be
lower
Each of us weighs a tiny bit less inside the ground floor of a skyscraper than we do on the ground away from the skyscraper because the
mass of the building above slightly attracts us upward
The amount of gravitational force that acts on a space vehicle while in Earth orbit is
nearly as much as the vehicle's weight on Earth's surface
There would be only one ocean tide per 24-hour day if the
none of the above (Earth and moon were equally massive, moon were more massive than the Earth, sun's influence on the tides were negligible, moon's mass were small - only a few kilograms)
Two planets in space gravitationally attract each other. If both their masses and the distance between them are doubled, the force between them is
none of the above (twice as much as before, half as much as before, 1/4 as much as before, four times as much as before)
If the Sun became twice as massive, your attraction to the Sun would double and your weight as measured on Earth would
not change
The main reason ocean tides exist is that the Moon's pull is stronger
on water closer to it than on water farther away
Earth is presently accelerating toward the Sun (centripetal acceleration). If the Sun collapsed into a black hole, this acceleration would
remain the same
If you drop a stone into a hole drilled all the way to the other side of Earth (neglect the molten core and any air along the way), the stone will
speed up until it gets to Earth's center
The force of gravity acting on you will increase if you
stand on a planet with a shrinking radius
Which of these three produces the greatest tidal effect on you right now?
the earth
Planets wobble in their orbits due to
the gravitational attraction to other planets
Which produces a greater tidal effect in your body: the Moon or a 1-kg melon held at arm's length above your head?
the melon
If you bounce and jump up and down on a bathroom scale, what varies on the scale reading is
the normal force
A black hole
the remains of a giant star that has undergone gravitational collapse.
A black hole is
the remains of a giant star that has undergone gravitational collapse.
Which pulls on the oceans of the Earth with a greater force?
the sun
Tidal forces in general are the result of
unequal gravitational forces acting on different parts of a body
In comparison with other fundamental forces, the universal gravitational constant G indicates that gravity is
very weak
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
winter
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
without support forces
Half-way to the center of a completely hollow planet with a thin uniform shell, your weight would be
zero