physics gravity

why did Newton think that a force must act on the moon

the moon orbits the earth

What did newton conclude about the force that brings apples to the ground and the force that holds the moon in orbit

gravity

If the moon falls why doesn't it get closer to the earth

satalittes fall around the earth

what is meant by tangental velocity

the velocity of a salattlie

since the planets are pulled around the sun by gravitational attraction why don't they crash into the sun

has to have a minimum Tangental velocity

What does the very small value of gravitational constant G tell us about the strength of gravitational forces

gravity is considered a weak force

what are two masses and one distance that equals your weight

your mass would be m1 the planet would me m2 and the dstance bewteen you is the radius

In what way in gravity reduced with distance from the earth

you want to increase you distance

what makes the earth go round

gravity

The earth and the moon are gravitationally attracted to each other does the more massive earth attract the moon with the greater force the same or less that the moon attracts the earth

Equal but opposite

If the gravitational forces of the sun of the planets suddenly disappeared in what kind of paths would the planets move

tangent to the path

which requires more fuel a rocket going from the earth to the moon or a rocket coming from the moon to earth

it is harder t to go away from the earth

we can think of a field force as a kind of extended aura that surrounds a body spreading its influence to affect things. As later chapters will show you an electric field affects electric charges and magnetic fields effect magnetic poles what does a gravi

mass

upon what quantities does the acceleration of gravity on the surface of various planets depend on

constant mass and the radius

how does the gravitational field surrounding earth vary with increasing distance

decreases

what is the value of the gravitational force at the center of the earth

0m/s/s

Which for pair is greater that between the moon and the earth or that between the sun and the earth

the sun and the earth

which is more effective in raising ocean tides the moon or the sun

the moon

what are two major factors that determine the size of a star

gravity and fusion

why would the earth not become a sun if it got sucked into a black hole

black holes still have mass

If the earth was the same size but twice as massive how would the value of G change if at all?and how would the value g change at all

it wouldnt big G stays the same it is a constant little g double

If the radius of earth somehow shrunk by half without without any change in earths mass what would the value of g be at the new surface

increases by 4 times as much

how does the direction of motion satellite in circular orbit compare with the curve of earths surface

equal

What is Keplers first law of planetary motion

elipses

does the period of satellite increase or decrease as its distance from the earth increases which of Keplers laws does not support

increases

Where in an elliptical orbit is the speed of statllite maximum minimum which of keplers three laws does this support

when it is the closest,when it is farthest away
2nd law

does the speed of a satellite around the earth depend on mass ?its distance from the earth? the mass of the earth ?

no yes yes

if you stopped an earth satellite dead in its tracks it would simply crash into the earth why then don't the communication satellites that hover motionless above the same spot on earth and not crash

they have the same time or same period