Download Physics - Gravity and Gravity Applications

Physics - Gravity and Gravity Applications
Name ________________________
1) Upon what quantities does the acceleration of gravity on the surfaces of various
planets depend?
2) Where is your weight greatest – at the surface of the earth, deep below the surface, or
above the surface?
3) Why would your weight be less if you were deep beneath the earth’s surface?
4) What is the value of the gravitational field at the center of the earth?
5) If you stepped into a hole bored completely through the earth and made no attempt to
grab the edges at either end, what kind of motion would you experience?
6) If the gravitational pull of the moon on the earth were the same over all parts of the
earth, would there be any tides? Defend your answer.
7) Which force-pair is greater – that between the moon and earth, or that between the sun
and earth?
8) Which is more effective in raising ocean tides – the moon or the sun? Explain.
9) Why are tides greater at the times of the full and new moons?
10. Distinguish between spring tides and neap tides.
11) Some people say that the full moon affects our bodies like it affects the oceans since
our bodies are mostly water. As a result, this makes us a little crazy during times of a full
moon. Is this a valid ascertain? Why or why not?
12) Astronauts who spend long periods in outer space could be adversely affected by
weightlessness. One way to simulate gravity is to shape the spaceship like a cylindrical
shell that rotates, with the astronauts walking on the inside surface. Explain how this
simulates gravity.
13) Why will orbiting space stations that simulate gravity likely be large structures?
(Remember what high RPMs do to the body’s inner ear)
14) A space station is rotating to create artificial gravity. Its period of rotation is chosen
so the outer ring (ro =2150 m) simulates the acceleration of gravity on earth (9.80 m/s2).
What should be the radius ri of the inner ring, so it simulates the acceleration of gravity
on the surface of Mars (3.72 m/s2)?
15) An exotic finish to massive stars is that of a neutron star which might have as much
as five times the mass of our Sun (Sun’s mass = 2.0 x 1030 kg), packed into a sphere
about 10 km in radius! Estimate the surface gravity on this monster.