Chapter 14

An object dropped from rest almost infinitely far from earth will fall to earth and strike the surface with about what speed ?

11.2 km/s

What is the scape speed from the surface of the earth?

11.2km/

What is escape speed from the surface of earth in km/s?

11.2km/s

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?

29 days

The curvature of the earth is such that for every 8000m tangent to the surface , the surface drops by how much?

4.9/5 m

What is the orbital speed in m/s for a satellite orbiting close to earths surface?

8000m/s

What is the period of a satellite that orbits close to earth?

90 minutes

Describe how to draw an ellipse using a piece of paper, pen, , two thumbtacks , and a piece of string.

A pair of tacks is used at each focus with a string and pen. The closer the foci are to eachother, the closer the ellipse is a circle

A circle is a special case of what geometric figure?

An ellipse

At what point does a satellite in an elliptical orbit have the greatest kinetic energy?

At the point closest to the planet(perigee)

How can some satellites in orbit around the earth stay above the same point on the equator all the time?

Because they are launced inyo orbit in the same plane as the equator

What determines the orbital speed of a planet?

Distance frome the star; stars mass

The force of gravity can do work on a satellite when it is in what kind of orbit?

Elliptical orbit

Give to reasons why Pluto takes a longer time to travel around the sun than the earth takes to travel the sun.

It has further to go and its slower

Define a satellites period.

It is the time for a satellite to make one complete revolution around earth

A projectile is fired vertically from the surface of earth at 10km/s. What will happen to the projectile?

It will rise and then fall back to earths surface at 10km/s

At what point does a satellite in a circular orbit have the greatest kinetic energy?

Its KE and PE are constant

The early bird communications satellite hovers over the same point on earths equator in definently. What is it's orbital period?

Its orbital period is 24 hours

Minimal orbital speed about the earth is approximately 8km/s. Would the minimal orbital speed about the moon be less or greater?

Less than 8km/s because its less massive

Compared to the period of a satellite in orbit close to earth is the period of a satellite in orbit far from earth longer or shorter? Why?

Longer, because if yhe location of the sattelite

Is the speed of a satellite in an elliptical orbit constant? explain.

No more speed= less distance More distance= less speed

Does the sun of a satellites KE and PE vary as the satellite orbits a planet ?

No remains constant

Because a satellite is always changing direction, does it lose energy as it orbits the earth?

No, energy is conserved there is no friction

Does the speed of a satellite in a circular orbit around the earth change as it circles the earth?

No, its alwahs constant

What is the term for the satellite uses to completely orbit the earth ?

Period

If a satellites orbital height is increased what happens to its orbital speed and period?

Speed goes down period goes up

Define perigee.

The point in the orbit of the moon or a satellite is closest to earth

Define apogee.

The point in the orbit of the moon or satellite is farthest to earth

What can you say about the speed of a satellite in a circular orbit?

The speed is not changed by gravity

Why do all sattelites orbit at least 150lm above the surface of the earth?

The speed is noy changed by gravity or else the atmopshperic friction would burn you to a crisp

Does a satellite orbiting earth have constant speed ? Constant radius? Constant acceleration?

They all change in an eliptical orbit

Which of a satellites kinetic, potential, or total energies , remain constant in an elliptical orbit?

Total energy us conserved

An object is placed exactly halfway between earth and the moon. Which way will the object fall? Why?

Towards earth , that has a stronger gravitatiobal force

Is an earth satellite a projectile?

Yes

Is it possible for a rocket to leave the surface of the earth and travel to the moon without its speed ever reaching the earths escape speed?

Yes

Will a vertically oriented rocket that maintains a continuous upward velocity of 8km/s escape earth?

Yes