Ch5_2
New Problems
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Make sure to calculate your answers in SI units unless specified otherwise .
1) Simulate artificial gravity in a tube shaped space station with a
m
radius far from earth (earth's gravitational pull is negligible) . Choose the tangential velocity of a point on the tube such that artificial gravity of
g
results (
g
is the gravitational acceleration close to the surface of the earth)
(see sheet 14,14')
. Indicate with a negative (positive) sign whether the occupants of the station walk on the wall at the inner (outer) radius.
2) The coefficient of friction for the tire-road interface of a car is . What is the maximum speed in
km/hr
the car can have in a curve with a
m
radius of curvature on a level road (not banked) before the car slides off the road
(see sheet 16-18)
? Indicate with a negative (positive) sign whether this velocity is larger (smaller) with everything the same except the road being banked
(see sheet 16,19)
.
3) A bobsled at
km/hr
turns around a curve with a
m
radius of curvature on a banked ice track. What is the banking angle if banking alone (friction neglected) is to hold the sled on its track
(see sheet 19,20)
? Indicate with a negative (positive) sign whether the banking angle increases (decreases) with increasing speed.
4) A planet has a radius of x10
6
m
and a mass of x10
24
kg
. What is the gravitational acceleration close to its surface
(see sheet 21,22,25)
? Indicate with a positive (negative) sign whether your calculated value depends (does not depend) on the chemical composition of the planet.
5) A rocket passes the earth at a large distance, of the order of earth radii. The gravitational acceleration due to the earth at this distance is
g
(
g
is the gravitational acceleration close to the surface of the earth; use 6.0x10
24
kg
for the earth mass.) How far is the rocket from the center of the earth
(see sheet27,27')
? Indicate with a negative (positive) sign whether the gravitational acceleration varies strongly (hardly at all) with distance changes from the surface of the earth which are of the order of a few
kilometers
.
6) A satellite circles the earth at a height of
km
above the surface of the earth. How many hours does it take the satellite to circle the earth
(see sheet 31)
(
use 6.0x10
24
kg
and
6.4x10
6
m
for the earth mass and radius) ?
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cannot resubmit answers
for the same Problem Set--you must use the 'New Problems' button first.