Physics 21.5 Satellite Motion

Question 1

What is Kepler’s Third Law?

Answer 1

The square of the period of a planet’s orbit is directly proportional to the cube of its mean distance from the Sun

Question 2

What is the equation linking orbital period and speed?

Answer 2

v=sqrt((GM)/r)

Question 3

Define orbital period

Answer 3

The time taken for a satellite to complete one full orbit is known as the orbital period, T

Question 4

What is the Kepler’s Third Law equation?

Answer 4

T^2 α r^3

Question 5

What is a synchronous orbit?

Answer 5

A synchronous orbit is one in which an orbiting object has an orbital period equal to the rotational period of the object it is orbiting.

Question 6

What is a geosynchronous orbit?

Answer 6

A geosynchronous orbit is an Earth-centred orbit with an orbital period equal to one day (the rotational period of the Earth)

Question 7

What is a geostationary orbit?

Answer 7

A geostationary orbit is an orbit that is always above the same point on Earth.

Question 8

What are the conditions for geostationary orbit?

Answer 8

• equatorial orbit
• moving West to East
• 24 hour orbital period

Question 9

What is the equation for the kinetic energy of a satellite?

Answer 9

Ek=((GMm)/2r)

Question 10

What is the equation for the gravitational potential of a satellite?

Answer 10

V=-(GM/r)

Question 11

What is the equation for the gravitational potential energy of a satellite?

Answer 11

Ep=-((GMm)/r)

Question 12

What is the overall energy of a satellite?

Answer 12

E=Ep+Ek

Question 13

What is the full equation for the total energy of a satellite in orbit?

Answer 13

E=-(GMm)/2r