Physics ch. 9 test
A very massive object A and a less massive object B move toward each other under the influence of gravitation. Which force, if either, is greater?
both forces are the same
A supplier wants to make a profit by buying metal by weight at one altitude and selling it at the same price per pound at another altitude. The supplier should . . .
buy at a high altitude and sell at a low altitude
An earth satellite is in an elliptical orbit. The satellite travels fastest when it is . . .
closest to the earth
how does the minimum orbital speed on other planets or moons compare to the minimal orbital speed required for an Earth satellite?
depends on their mass
According to Kepler's laws, the paths of the planets about the sun are . . .
ellipses
in which type of orbit, circular or elliptical, does the gravitational force do work on the satellite?
elliptical
where does a satellite in circular orbit have the greatest kinetic energy? the least kinetic energy?
everywhere is the same
During an eclipse of the sun the high ocean tides on earth are . . .
extra high
If the mass of the earth somehow increased with no change in radius, your weight would . . .
increase also
A woman on the surface of the earth has a mass of 50 kilograms and a weight of 500 newtons. If the woman were floating freely inside a space habitat far away from earth, she would have . . .
less weight and the same mass
A "weightless" astronaut in an orbiting shuttle is . . .
like the shuttle, pulled by earth's gravitation
Minimal orbit speed about the earth is about 8000 m/s (8 km/s). Minimal orbital speed about the Jupiter would be . . .
more than 8000 m/s
Which pulls on the oceans of the earth with the greater force?
the sun
Planets would crash into the sun if it weren't for . . .
their tangential velocities
do any of the following remain constant for a satellite in circular orbit: kinetic, potential energy, total energy, velocity, orbital radius? List all apply
yes, all
A woman who normally weighs 400 N stands on top of a very tall ladder so she is one earth radius above the earth's surface. How much would she weigh there?
100 N
what is the force of gravity of a 100N object on Mars?
100N
what is the minimum altitude required for an Earth satellite? That is, how far above Earth's surface must a satellite be be located to orbit successfully?
150km
how far does the surface of the Earth "drop" vertically if you measure an 8000m line tangent to the surface?
5m
what is the orbital speed of a satellite that orbits close to Earth's surface in m/s and km/s?
8000m/s, 8km/s
Consider this diagram (the dot on the left is B and the dot on the right is A): where does the satellite have maximum gravitational attraction?
A
Consider this diagram (the dot on the left is B and the dot on the right is A): where does the satellite have maximum kinetic energy?
A
Consider this diagram (the dot on the left is B and the dot on the right is A): where does the satellite have maximum momentum?
A
Consider this diagram (the dot on the left is B and the dot on the right is A): where does the satellite have maximum velocity?
A
Consider this diagram (the dot on the left is B and the dot on the right is A): where is the perigee?
A
A satellite in an elliptical orbit travels at constant . . .
none of the above
There are no tides to be seen in the community swimming pool because . . .
all parts of it are practically the same distance from the moon
where does a satellite in circular orbit have the most kinetic energy and the least kinetic energy?
all the same at all points
The amount of gravitational force that acts on the space shuttle while in orbit is . . .
almost as much as the shuttle's weight on the earth's surface
describe the spatial relationship between the gravitational force and tangential velocity vectors for a satellite in an elliptical orbit?
at varying degrees. component of gravity force changes the planets speed
Consider this diagram (the dot on the left is B and the dot on the right is A): where does the satellite have maximum potential energy?
B
Consider this diagram (the dot on the left is B and the dot on the right is A): where is the apogee?
B
why does Earth's moon play a larger role in creating tides than the sun?
Earth's moon is much closer and affects one side of more than the other
is energy conserved for satellite in circular orbit?
yes
How does the gravitational potential energy of a satellite in circular orbit change over the course of one revolution?
it doesn't change
how does kinetic energy of a satellite in circular orbit change over the course of one revolution>
it doesn't change
how does the speed of a satellite in circular orbit change over the course of one revolution?
it doesn't change
How does the gravitational potential energy of a satellite in an elliptical orbit change over the course of one revolution?
it goes up and down
how does the kinetic energy of a satellite in an elliptical orbit change over the course of one revolution?
it goes up and down
how does the speed of a satellite in an elliptical orbit change over the course of one revolution?
it goes up and down
what will happen to a projectile fired vertically from Earth's surface if... the launch speed is less than Earth's escape velocity?
it will fall back down to Earth
what will happen to a projectile fired vertically from Earth's surface if... the launch speed is greater than Earth's escape velocity?
it will leave Earth's orbit
what will happen to a projectile fired vertically from Earth's surface if... the launch speed is equal to Earth's escape speed?
it will orbit Earth
Minimal orbit speed about the earth is about 8000 m/s (8 km/s). Minimal orbital speed about the moon would be . . .
less than 8000 m/s
What prevents satellites such as the space shuttle from falling?
nothing, they continually fall all around the earth
Communications and weather satellites always appear at the same place in the sky. This is because these satellites are . . .
orbiting the earth with a 24 hour period
The force of gravity acting on you will increase if you . . .
stand on a planet with a radius that is shrinking
The earth is presently accelerating toward the sun (centripetal acceleration). If the sun collapsed into a black hole, this acceleration would . . .
stay the same
Which is most responsible for the ocean tides?
the moon
describe the spatial relationship between the gravitational force and tangential velocity vectors for satellite in circular orbit
they are perpendicular 90 degrees (temp has no effect on velocity)
If the satellite followed a circular orbit rather than an elliptical orbit what would happen to all of the forces (KE, PE, gravitational attraction, , momentum, velocity)?
they would all be equal
Tidal forces in general are the result of . . .
unequal forces acting on different parts of a body
does the gravitational force do work on a satellite in an elliptical orbit?
yes
