PHYS chpt. 9
A weight watcher who normally weighs 400 N stands on top of a very tall ladder so she is one Earth radius above the Earth's surface. How much would she weigh there?
100N
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
40N
What is the force of gravity on a 500-newton woman standing on the Earth's surface?
500 N
A very massive object A and a less massive object B move toward each other under the influence of gravitation. Which force, if either, is greater?
BOTH, forces A and B
An object is placed exactly halfway between the Earth and moon. The object will fall toward the...
Earth
Einstein's theory of gravitation, compared with Newton's,
Eliminates the role of force
How far must one travel to get away from the Earth's gravitational field?
FORGET IT; you can't travel far enough.
Two objects move toward each other because of gravity. As the objects get closer and closer, the force between them...
Increases
Consider two planets in space that gravitationally attract each other. If the masses of both planets are doubled, and the distance between them is also doubled, then the force between them is...
NONE OF THESE! four times as much twice as much. one quarter. half as much.
What happens to the force of attraction between two planets when the distance between them is doubled?
The force decreases to one quarter
Is gravitational force acting on a person who falls off a cliff?
Yes
Is gravitational force acting on an astronaut inside an orbiting space shuttle?
Yes
The amount of gravitational force that acts on the space shuttle while in orbit is...
almost as much as the shuttle's weight on the Earth's surface.
No force due to Earth's gravity is acting on the astronauts inside the orbiting space shuttle. This statement is...
always false
Inside a freely falling elevator, there would be no...
apparent weight for you
Inside a freely falling runaway elevator, your...
apparent weight is zero
The Earth's gravitational field extends...
both inside and outside the Earth and throughout the entire universe.
Black holes are essentially...
collapsed stars
If the Earth's mass decreased to one-half its original mass with no change in radius, then your weight would...
decrease to one half your original weight.
According to Newton, doubling the distance between two interacting objects...
divides by 4 the gravitational force between them
The value of g at Earth's surface is about 9.8 m/s^2. What is the value of g at a distance of twice Earth's radius?
g=2.5m/s^2
If the mass of the Earth somehow increased with no change in radius, your weight would...
increase also
The main reason ocean tides exist is that the pull of the moon...
is greater on oceans closer to the MOON and less on oceans farther from the moon.
A hollow spherical planet is inhabited by people who live inside it, where the gravitational field is zero. When a very massive space ship lands on the planet's surface, inhabitants find that the gravitational field inside the planet is...
non-zero, directed TOWARD the spaceship.
The force of gravity acts on all apples on an apple tree. Some apples are twice as far from the ground as others. These twice-as-high apples, for the same mass, have...
practically the same weight
When a star collapses to form a black hole, its mass...
remains the SAME
A black hole is...
simply the remains of a giant star that has undergone gravitational collapse.
The factor most directly responsible for making a black hole invisible is its...
surface escape velocity
Which is most responsible for the ocean tides?
the MOON
Which pulls on the oceans of the Earth with the greater force?
the SUN
Newton discovered...
the gravity is universal
An asteroid exerts a 360-N gravitational force on a nearby spacecraft. This force is directed...
toward the asteroid.
Half way to the center of a completely hollow planet with a thin uniform shell, your weight would be...
zero