2. Gravity
A natural phenomenon by which all things with
mass are brought toward one another, including
planets, stars and galaxies.
*Mass is defined as the amount of matter in an
object.
-More mass = more gravitational force
3. Newton’s Law of Universal Gravitation
Describes gravity as a force which causes any two bodies to be attracted
to each other, with the force proportional to the product of their masses
and inversely proportional to the square of the distance between them.
F = force, m1 and m2 are the masses of the objects interacting, r is the
distance between the centers of the masses and G is the gravitational
constant
4. General Theory of Relativity
Proposed by Einstein in 1915
● Describes gravity not as a force, but as a consequence
of the curvature of spacetime caused by uneven
distribution of mass/energy.
○ Most extreme example of this curvature of
spacetime is a black hole.
5.
6.
7. Why are astronauts weightless in space?
● For the same reasons that riders of a free-falling
amusement park ride or a free-falling elevator are
weightless. They are weightless because there is no
external contact force pushing or pulling upon their body.
● They aren’t floating, they are actually falling. They have
the same acceleration as the space station or spaceship,
they feel weightless.
8. Microgravity
● A condition in which people or objects appear to be
weightless
● Micro - very small
● There is gravity in space but it is very small. Gets weaker
with distance.
● Space is a vacuum which causes all objects to fall at the
same rate regardless of their mass.
