Astro 7N Exam 1 Questions (2025) Complete
Exam Questions and Answers | already graded A+
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Terms in this set (98)
The force of gravity by the They exert an equally strong pull on the sun, causing
Sun keeps the planet in it move slightly
orbit around it, but how
do the planets affect the
sun?
An object at rest stays at rest and an object in motion
stays in motion with the same speed and in the same
direction unless acted upon by an unbalanced force.
Newton's First Law
ex: if the sun suddenly disappeared, the Earth would
continue in the direction that it was traveling in its
orbit at that time
The acceleration of a body due to a force will be in
the same direction as the force, with magnitude
directly proportional to its mass
Newton's Second Law
Force = mass x acceleration
A smaller mas will move faster, if the same force is
applied to it
, For every action there is an equal and opposite
reaction
Newton's Third Law The Sun exerts force on planets, and they orbit it - he
planets exert equal force on Sun, but it only moves
slightly because of its very large mass relative to the
planets
the strength of gravity: g = m/r^2
where M is the mass of the planet and R is its radius.
Note the radius is squared but the mass is not.
More mass = more gravity.
- If the mass of a planet were twice that of another,
but they had the same radius, the gravity felt on the
surface of the more-massive one would be twice as
strong.
Larger separation = less gravity.
Surface Gravity on a
- If the radius of a planet were twice that of another,
Planet
the gravity is 1 / (2) 2 = 1/4 as strong.
Putting the effects of mass and radius together, you
should be able to figure out the surface gravity of
Mars, relative to the Earth.
- Mars has 1/10 the mass of the Earth and 1/2 the
radius of Earth. So for Mars,
g = (1/10) / (1/2) 2 = (1/10) / (1/4) = 4/10
Mars has a surface gravity 4/10 that of Earth. You will
need to be able to do this type of estimate for the
test, given the numbers for mass and radius.
If I apply exactly the same the pebble will move faster
amount of force to a
pebble and a boulder,
what will happen
,If the Earth were moved to it would become 4 times weaker
half its current distance
from the sun, how would
the force of gravity by the
sun on the earth change?
As the mass of the planet increases, the jump height
does decreases by the same factor
Mass
As the mass of the planet decreases, the jump height
does increases by the same factor
According to Newton's acceleration increases
Second law of motion, if
the net force acting on the
object increases while the
mass of the object remains
constant, what happens to
acceleration
If the earth were moves to it would become four times weaker
half its current distance
from the Sun, how would
the force of gravity by the
Sun on the Earth change
What did newton's law of the force of gravity from the sun will be stronger on
universal gravitation tell us object with more mass
about how gravity works
If you were to sit on the you are pushing the earth away from yourself with the
ground, there would be a same force
force due to gravity
pulling you toward the
earth. which of the
following is true according
to newton's third law
, what would happen to the it would continue to move in the line in the same
earth sun's gravity direction it was moving when the gravity turned off
somehow turned off
instantaneously
This law gives the force of gravity between any two
objects in the Universe. The force of gravity is
proportional to (mass of object 1) × (mass of object 2)
divided by the distance between the two objects
squared:
F M1 x M2 / d 2
Newton's Universal Law of
Gravitation
Again, more mass = stronger gravity. If the objects
were moved 2 times closer (or, to half of their initial
distance between), ...
F M1 x M2 / (1/2) 2 = M1 x M2 / (1/4) = 4 (M1 x M2)
... so, the gravitational attraction would become 4
times as great.
Exam Questions and Answers | already graded A+
Save
Terms in this set (98)
The force of gravity by the They exert an equally strong pull on the sun, causing
Sun keeps the planet in it move slightly
orbit around it, but how
do the planets affect the
sun?
An object at rest stays at rest and an object in motion
stays in motion with the same speed and in the same
direction unless acted upon by an unbalanced force.
Newton's First Law
ex: if the sun suddenly disappeared, the Earth would
continue in the direction that it was traveling in its
orbit at that time
The acceleration of a body due to a force will be in
the same direction as the force, with magnitude
directly proportional to its mass
Newton's Second Law
Force = mass x acceleration
A smaller mas will move faster, if the same force is
applied to it
, For every action there is an equal and opposite
reaction
Newton's Third Law The Sun exerts force on planets, and they orbit it - he
planets exert equal force on Sun, but it only moves
slightly because of its very large mass relative to the
planets
the strength of gravity: g = m/r^2
where M is the mass of the planet and R is its radius.
Note the radius is squared but the mass is not.
More mass = more gravity.
- If the mass of a planet were twice that of another,
but they had the same radius, the gravity felt on the
surface of the more-massive one would be twice as
strong.
Larger separation = less gravity.
Surface Gravity on a
- If the radius of a planet were twice that of another,
Planet
the gravity is 1 / (2) 2 = 1/4 as strong.
Putting the effects of mass and radius together, you
should be able to figure out the surface gravity of
Mars, relative to the Earth.
- Mars has 1/10 the mass of the Earth and 1/2 the
radius of Earth. So for Mars,
g = (1/10) / (1/2) 2 = (1/10) / (1/4) = 4/10
Mars has a surface gravity 4/10 that of Earth. You will
need to be able to do this type of estimate for the
test, given the numbers for mass and radius.
If I apply exactly the same the pebble will move faster
amount of force to a
pebble and a boulder,
what will happen
,If the Earth were moved to it would become 4 times weaker
half its current distance
from the sun, how would
the force of gravity by the
sun on the earth change?
As the mass of the planet increases, the jump height
does decreases by the same factor
Mass
As the mass of the planet decreases, the jump height
does increases by the same factor
According to Newton's acceleration increases
Second law of motion, if
the net force acting on the
object increases while the
mass of the object remains
constant, what happens to
acceleration
If the earth were moves to it would become four times weaker
half its current distance
from the Sun, how would
the force of gravity by the
Sun on the Earth change
What did newton's law of the force of gravity from the sun will be stronger on
universal gravitation tell us object with more mass
about how gravity works
If you were to sit on the you are pushing the earth away from yourself with the
ground, there would be a same force
force due to gravity
pulling you toward the
earth. which of the
following is true according
to newton's third law
, what would happen to the it would continue to move in the line in the same
earth sun's gravity direction it was moving when the gravity turned off
somehow turned off
instantaneously
This law gives the force of gravity between any two
objects in the Universe. The force of gravity is
proportional to (mass of object 1) × (mass of object 2)
divided by the distance between the two objects
squared:
F M1 x M2 / d 2
Newton's Universal Law of
Gravitation
Again, more mass = stronger gravity. If the objects
were moved 2 times closer (or, to half of their initial
distance between), ...
F M1 x M2 / (1/2) 2 = M1 x M2 / (1/4) = 4 (M1 x M2)
... so, the gravitational attraction would become 4
times as great.
