chapter 14 satellite motion
satellite
a projectile moving fast enough to fall continually around earth rather than into it
perpendicular, parallel
a satellite in circular orbit around earth is always moving __________ to gravity and _______ to earth's surface at constant speed
800, 5
a stone is thrown fast enough to go a horizontal distance of ___ meters during the time (1 second) it takes to fall ____ meters, will orbit earth
A satellite near earth makes a full circle in about an hour and a half. how long would it take a satellite located as far away as the moon to orbit earth? a) about 28 days b) a satellite could not be put into such an orbit c) it depends on the mass of the satellite d) about an hour and a half e) none of the above
a) about 28 days
Where does a satellite in an elliptical orbit have the greatest kinetic energy? a) at the point closest to the planet b) exactly at the point halfway to the planet c) at the point farthest from the planet d) anywhere- its kinetic energy is constant e) more information needed
a) at the point closest to the planet
The speed of a satellite in a circular orbit is... a) constant b) not constant c) constantly increasing
a) constant
The Earlybird communications satellite hovers over the same point on Earth's equator indefinitely. This is because... a) its orbital period is 24 hours b) it is beyond the main pull of gravity c) it pulls as hard on Earth as earth pulls on it d) it is kept aloft by ground control e) forces other than Earth's gravity act on it
a) its orbital period is 24 hours
Minimal orbital speed about Earth is approximately 8km/s. Minimal orbit speed about the moon would be... a) less than 8km/s b) about 8km/s c) more than 8 km/s
a) less than 8 km/s
A projectile is fired vertically from the surface if earth at 10 km/s. The projectile will... a) rise and then fall back to Earth's surface b) go into an elliptical orbit about Earth c) go into a circular orbit about earth d) none of the above
a) rise and then fall back to Earth's surface
The force of gravity does work on a satellite when it is in... a) circular orbit b) elliptical orbit c) both A and B d) neither A nor B
b) elliptical orbit
A vertically oriented rocket that maintains a continuous upward velocity of 8 km/s will... a) not be able to escape earth b) escape earth
b) escape earth
Compared to the period of a satellite in orbit close to earth, the period of a satellite in orbit far from earth is... a) the same b) longer c) shorter d) not enough enformation
b) longer
The speed of a satellite in an elliptical orbit is... a) independent if the height if the satellite b) not constant c) constant
b) not constant
An object dropped from rest almost infinitely far from Earth falls to Earth because of Earth's gravitational field, and strikes the surface with a speed of about... a) 8 km/s b) 9.8 km/s c) 11 km/s d) none of the above
c) 11 km/s
Escape speed from the surface of Earth is about... a) 8 km/s b) 9.8 km/s c) 11.2 km/s d) 16 km/s e) it is impossible to completely escape from Earth
c) 11.2 km/s
The curvature of Earth is such that for every 8000 m tangent to the surface, the surface drops about... a) 0m b) 2.5m c) 5m d) 10m e) 20m
c) 5m
The orbital speed for a satellite orbiting very close to Earth's surface is... a) 1600 m/s b) 4900m/s c) 8000 m/s d) 16,000 m/s e) 80,000 m/s
c) 8000 m/s
A circle is a special case of... a) a hyperbola b) a parabola c) an ellipse d) a focus
c) an ellipse
The reason satellites orbit Earth at least 150 km above the surface is to... a) be above Earth's gravity b) make sure they are higher than the highest mountains c) be above Earth's atmosphere d) keep them out of the way of commercial airliners e) all of the above
c) be above earth's atmosphere
What remains constant for a satellite in an elliptical orbit? a) its speed b) Its potential energy c) its total energy d) its kinetic energy e) its distance from the planet
c) its total energy
A period of a satellite is defined as... a) the time for a satellite to cross the United States b) 1 second c) the time for a satellite to make one complete revolution around Earth d) 90 seconds e) 24 hours
c) the time for a satellite to make on complete revolution around Earth
The circular orbit of a satellite orbiting Earth is characterized by a constant... a) speed b) radius c) magnitude of acceleration d) all of the above e) none of the above
d) all of the above
Where does a satellite in a circular orbit have the greatest kinetic energy? a) at the point farthest from the planet b) exactly at the point halfway to the planet c) at the point closest to the planet d) anywhere- its kinetic energy is constant e) more information is needed
d) anywhere- its kinetic energy is constant
The higher satellite is, the... a) less its speed is b) greater its speed is c) longer its period is d) both A and C e) both B and C
d) both A and C
The fastest moving planet in a solar system is... a) the most massive planet b) any planet (they all move at the same speed) c) the smallest planet d) the planet nearest the sun
d) the planet nearest the sun
pioneer 10
first probe to escape the solar system
one, inside or outside
for a satellite orbiting a planet, the center of the planet is at ___ focus and the other focus could be ___ or _____
less, longer
for higher altitudes, the orbital speed is ____ and the period is ____
why doesn't the gravity that acts on the bowling ball change its speed?
gravity is pulling neither forward nor backward-it pulls straight downward, perpendicular to the ball's motion. The bowling ball has no component of gravitational force along the direction of the alley
62 MJ/kg, 11.2 km/s
if we give a payload any more energy than ___ at the surface of earth or, equivalently, any greater speed than ___, then, neglecting air resistance, the payload will escape from earth never to return
yes
isn't there some vertical speed that is sufficient to ensure that what goes up will escape and not come down ?
11.2 km/s
neglecting air resistance, fire anything at any speed greater than ___, and it will leave earth, going more and more slowly, but never stopping
constant, varies
satellite speed, which is ______ in circular orbit, ___ in an elliptical orbit
kepler's second law
states that each planet moves so than an imaginary line drawn from the sun to any planet sweeps out equal areas of space in equal intervals of time
kepler's first law
states that the path of each planet around the sun is an ellipse with the sun at one focus
kepler's third law
states that the square of the orbital period of a planet is directly proportional to the cube of the average distance of the planet from the sun
infinite
the PE is NOT ____ because the distance is infinite
greatest, least
the PE is ___ when the satellite is at the apogee and _____ when the satellite is at the perigee
ellipse
the closed path taken by a point that moves in such a way that the sum of its distances from two fixed points is constant
escape speed
the minimum speed necessary for an object to escape permanently from a gravitational field that holds it
perigee
the point in a satellite's orbit closest to the center of earth
apogee
the point in a satellite's orbit farthest from the center of earth
KE, PE
the sum of ____ and ___ of a satellite is constant at all points along an orbit
period
the time required for a complete orbit; 90 minutes
foci
the two fixed points on an ellipse
62 million juuls
the value of PE for a 1-kilogram mass infinitely far away is _______
Kepler's law of planetary motion
three important discoveries about planetary motion that were made by the german astronomer Johannes Kepler k
8 km/s
when the initial speed is over ___, the satellite overshoots a circular path and moves away from earth, against the force of gravity