Universal Gravitation

The force on a ball decreases as the ball moves farther from earth.

True

Suppose the gravitational force between two massive spheres is 10 N. If the distance between the spheres is cut in half, what is the force between the masses? a) 40 N b) 2.5 N c) 5 N d) 20 N e) 10 N

a) 40 N

Which is more, the gravitational force between earth and the moon, or between earth and the sun? a) earth-sun b) equal c) earth-moon

a) earth-sun

Newton had the insight to see that the ___________. a) force on the moon has the same nature as the force on an apple b) moon is moving c) moon orbits earth d) moon always keeps one side toward earth e) none of the above

a) force on the moon has the same nature as the force on an apple

If the mass of earth increased, with no change in mass, your weight would __________. a) increase also b) stay the same c) decrease

a) increase also

The force of gravity acting on you will increase if you ________. a) stand on a planet with a radius that is shrinking b) burrow deep inside the planet c) both a and b d) none of the above

a) stand on a planet with a radius that is shrinking

If the radius of earth decreased, with no change in mass, then your weight would __________. a) not change b) increase c) decrease

b) increase

A lunar month is about 28 days. If the moon were closer to earth than it is now, the lunar month would be _______. a) unchanged at 28 days b) less than 28 days c) more than 28 days

b) less than 28 days

Each of us weighs a tiny bit less on the ground floor of a sky scraper than we do on the top floor. One reason for this is that __________. a) the gravitational field is shielded inside the building b) the mass of the building attracts you upward slightly c) both a and b d) none of the above

b) the mass of the building attracts you upward slightly

According to Newton's laws, a rock and a pebble will fall at the same acceleration in a gravitational field because ___________. a) the gravitational force on each is the same b) the ratio of force/ mass is the same for both c) both a and b d) none of the above

b) the ratio of force/mass is the same for both

Suppose the gravitational force between two massive spheres is 10 N. If the distance between the spheres is doubled, what is the force between the masses? a) 10 N b) 20 N c) 2.5 N

c) 2.5 N

If earth's mass decreased to one half its original mass, with no change in radius, then your weight would _____. a) stays the same b) decreased to one half your original weight c) decreased to one quarter your original weight d) none of the above

c) decreased to one quarter your original weight

Because Earth is "falling" around the sun, it will eventually crash into it.

false

Because earth and moon are gravitationally attracted towards each other, they will soon collide.

false

If earth were to disappear, the moon would still orbit the place where earth was.

false

the force of attraction between two masses. . ..

false

There is a force on earth that is directed toward the sun.

true

some scientists think that the universe we live in is oscillating.

true

the component of an orbiting satellite's velocity that is parallel to earth's surface is its tangential velocity.

true

If earth were its present size but twice as massive, we would weigh less.

False

A supplier wants to make a profit by buying metal by weight at one altitude and selling it at the same price per pound at another altitude. The supplier should ________. a) buy at low altitude and sell at a high altitude b) buy at a high altitude and sell a low altitude c) disregard altitude because it has a negligible effect

c) disregard altitude because it has a negligible effect

Two objects move toward each other because of gravitational attraction. As the objects get closer, the force between them ________. a) decreases b) remains constant c) increases

c) increases

Jupiter has more than 300 times the mass of earth. Yet on Jupiter's surface an object weighs only about 3 times as much as it would on earth. The explanation to this involves Jupiter's _______. a) greater distance from the sun b) low density c) large radius

c) larger radius

Newton reasoned that the gravitational attraction between earth and the moon must be ___________. a) the same at all distances b) independent of distance c) reduced by distance d) directly proportional to distance e) all of the above

c) reduced by distance

The reason the moon does not fall into the earth is that _______. a) gravitational pull of other planets keeps the moon up b) earth's gravitational field at the moon is weak c) the moon has a sufficiently large orbital speed d) the moon has less mass than the earth e) none of the above

c) the moon has sufficiently large orbital speed

Suppose the gravitational force between two masses is 10 N. IF the volume of each mass doubles, while everything else stays the same, what is the force between the masses? a) 20 N b) 15 N c) 5 N d) 10 N

d) 10 N

Newton hypothesized that the moon ________. a) has tangential velocity that prevents it from falling into earth b) is a projectile c) is falling around earth d) is actually attracted to the earth e) all of the above

e) all of the above