an object is placed exactly halfway between earth and the moon . the object will fall towards ......a. the moon b.earth c. neither earth nor moon
b earth
If the mass of Earth increased, with no change in radius, your weight would _______ . a. stay the same b. decrease c. increase also
C. Increase!
The gravitational force between two massive spheres a. is always an attraction. b. depends on how massive they are. c. depends inversely on the square of the distances between them. d. all of the above.
D. The gravitational force is an attractive force that depends on the mass of two objects AND on the distance between them (squared)!
newton hypothesized that moon ... a is a projectile b. is falling around earth c . is actually attracted to earth d. all of the above
D . the moon is a projectile which is attracted towards earth and is falling around the earth
If the radius of Earth decreased, with no change in mass, your weight would _______ . a. not change b. increase c. decrease
B. Increase!
A very massive object A and a less massive object B move toward each other under the influence of mutual gravitation. Which force, if either, is greater? a. The force of A on B b. The force of B on A c. Both forces are the same
C. By Newton's Third Law, both forces are the same!
Newton reasoned that the gravitational attraction between the Earth and the moon must be __________ . a. reduced by distance b. independent of distance c. indirectly proportional to distance d. the same at all distances
A. Reduced by distance!
If Earth's mass decreased to one half its original mass, with no change in radius, then your weight would _________ . a. stay the same b. decrease to one half your original weight c. decrease to one quarter your original weight d. none of the above
B. Decrease to one half your original weight!
The force of gravity on you is greatest when you are standing: a. far above the Earth's surface b. just above the Earth's surface c. on the Earth's surface
C. On the earth's surface!
The reason the moon does not fall into Earth is that ______. a. Earth's gravitational field at the moon is weak b. the moon has a sufficiently large orbital speed c. the gravitational pull of other planets keeps the moon up d. the moon has less mass than Earth
B. Its orbital speed is large enough!
Two objects move toward one another because of gravitational attraction. As the objects get closer and closer, the force between them _________ . a. remains constant b. decreases c. increases
C. Increases!
Each of us weighs a tiny bit LESS on the ground floor of a skyscraper than we do on the top floor. This is because ___. 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. neither A nor B
B. The mass of the building attracts you upward slightly!
Since Earth is attracted to the sun, why doesn't it fall into the sun? a. It has too much mass to move toward the sun. b. It has a sufficiently large orbital velocity. c. There is an equal force holding it away from the sun. d. It has too much inertia to move toward the sun.
B. Its orbital velocity is large enough!
Suppose the gravitational force between two massive spheres is 100 N. If the distance between the spheres is doubled, what is the force between them? a. 400 N b. 200 N c. 100 N d. 50 N e. 25 N
E. 25 N
When in orbit, a satellite such as the space shuttle is: a. a projectile under the force of Earth's gravity b. experiencing non-acclerated motion b. free from Earth's gravity
A. Satellites are projectiles under the force of Earth's gravity!