Why does the vis viva equation, v^2=GM(1/r-2/a) give different velocities than v=SQRT(GM/r), and which is accurate?
on December 24th, 2009 | One answer

Using the vis viva equation appears to give inaccurate solutions. v^2=GM(2/r-1/a) The only time the solutions are correct is when a=r???
on December 23rd, 2009 | 3 answers

If our Sun were a black hole what would it's temperature be?
on December 9th, 2009 | One answer

Calculate the accelleration of the tides?
on December 9th, 2009 | One answer

How is the mass of the Sun determined?
on December 9th, 2009 | 3 answers | 1 person likes this

Comet tails show us radiation from the Sun is an appreciable force. Calculate the ratio of gravitational and radiation forces on a small...
on December 8th, 2009 | 4 answers | 2 people like this

A 5.5 Mev gamma ray is scattered at 60 degrees from an electron. In Mev, what is the energy of the scattered photon?
on December 8th, 2009 | One answer | 1 person likes this

At its peak, the Sun's spectrum is 484 nm, what is the surface temperature?
on December 8th, 2009 | 2 answers

At what speed is the kinetic energy of a particle equal to its rest energy?
on December 8th, 2009 | 3 answers | 2 people like this

2 protons with energy 10 keV collide head on. Assuming non-relativistic speeds how close do they approach each other?
on December 8th, 2009 | One answer

What velocity must a particle of rest mass mand velocity v have if its momentum is 10mv?
on December 8th, 2009 | One answer

An electron with a rets mass of 9.11 x10E-31 kg is accellerated to an energy of 30x10E9eV(GeV). Kinetic energy? Momentum? Speed?
on December 8th, 2009 | One answer

A 200m (rest length) space craft passes by a satellite in 8us, what is its speed relative to the satelite?
on December 8th, 2009 | One answer

A satellite in low earth orbit experiences drag reducing mechanical energy, by how much does this slow down its orbit due to friction?
on December 8th, 2009 | 2 answers

Excluding wind resistance and such, which angle would yeild a further distance for an arrow fired at 124 mps, 30 degrees or 60 degrees?...
on December 7th, 2009 | 4 answers | 2 people like this

A proton from rest falls through a potential difference of 25,000V, what speed does it gain?
on December 7th, 2009 | One answer | 1 person likes this

What is the maximum or burnout velocity of the Saturn V rocket whose mass was 2.45x10E6 kg, 65 percent of which is fuel, if the fuel...
on December 7th, 2009 | One answer | 1 person likes this

Aluminum rivets in airplanes are made larger than the holes they fit into and are cooled with dry ice before insertion to -78C. Warming...
on December 7th, 2009 | One answer | 1 person likes this

What is the activity of 1 gram of Cobalt 60 with a half life of 5.24 yrs?
on December 7th, 2009 | One answer | 1 person likes this

An Ice man was discovered with an activity of 14/6C Bq/g . How old is the iceman?
on December 7th, 2009 | One answer | 1 person likes this

A satelite ina circular orbit around Earth at a radius twice Earth's radius. 2Re.. How much energy is required to move it to an...
on December 7th, 2009 | 2 answers | 1 person likes this

The vis viva equation is designed to give a velocity for a specific portion of orbit. Why is it that if one uses periapsis for this point...
on December 7th, 2009 | One answer