Working With Equations Help File


Equation 1:

This equation allows you to find the energy of a moving object if its mass and velocity are known.

VARIABLES: E is Energy of the moving object (in Joules)
m is Mass of the moving object (in kilograms)
v is Velocity of the moving object (in meters per second)


Equation 2:

This equation allows you to find the scale height of a planet's atmosphere if the temperature and composition of the atmosphere, and the gravity of the planet is known.

VARIABLES: H is the scale height of the atmosphere (in meters)
k is the Boltzmann Constant ( = 1.38 x 10 -23 Joules/Kelvin)
T is the temperature of the atmosphere (in Kelvin)
μ is the mean molecular weight of the gas (in kilograms)
g is the gravity of the planet (in meters/second2)


Equation 3:

This equation allows you to find the amount of energy being emitted per second by an object with a given size and temperature. The term in parentheses is the surface area of a spherical object.

VARIABLES: L is Luminosity of the emitter (in Joules per second)
σis the Stefan-Boltzmann constant ( = 5.67 x 10 -8)
T is Temperature of the emitter (in Kelvin)
π is a constant ( = 3.1415926)
R is Radius of the emitter (in meters)


Equation 4:

This equation allows you to find the amount of energy being received per second by a square meter receiver from an object with a given luminosity at a given distance.

VARIABLES: F is Flux received (in Joules per second per square meter = Watts/meters2)
L is Luminosity of the emitter (in Joules per second = Watts)
π is a constant ( = 3.1415926)
d is Distance from the emitter (in meters)


Equation 5:

This equation allows you to find the surface area of a sphere if its radius is known.

VARIABLES: A is Surface Area of sphere (in square meters)
π is a constant ( = 3.1415926)
R is Radius of sphere (in meters)


Equation 6:

This equation allows you to find the escape velocity of an object if the mass and radius of the object are known.

VARIABLES: v is the Escape Velocity of an object (in meters/second)
G is the Gravitational Constant ( = 6.67 x 10 -11 meters3/(kilograms*seconds2))
M is the Mass of the object (in kilograms)
R is the Radius of the object (in meters)


Equation 7:

This equation allows you to find the surface gravity of an object if the mass and radius of the object are known.

VARIABLES: g is the Surface Gravity of an object (in meters/second2)
G is the Gravitational Constant ( = 6.67 x 10 -11 meters3/(kilograms*seconds2))
M is the Mass of the object (in kilograms)
R is the Radius of the object (in meters)



What can I do with these equations?

1. You Can Get a Relative Value for a Variable.

2. You Can Also Get an Absolute Numerical Value for a Variable.

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Working With Equations written by Dr. Douglas P. Hamilton Mike Asbury, and Amanda L. Proctor