physics
posted by Anonymous .
Mercury is an average distance of 5.79 x 107 km from the Sun. Estimate the length of the Mercurian year given that the Earth is 1.50 108 km from the Sun on the average.
An explanation of how to do this would be great, thanks.

Use Kepler's third law. There is a particuarly simple form of it
P^2 = a^3
if you measure the period (P) in years and the distance (a) in astronomical units (a.u.). The earth's distance from the sun is 1 au. Mercury's is 5.79*10^7/1.50*10^8 = 0.386 au
You will find the formula at
http://www.windows.ucar.edu/tour/link=/the_universe/uts/kepler3.html&edu=high
and probably also in your textbook.
Respond to this Question
Similar Questions

Physics
What is the average linear speed of Mercury about the Sun? 
Math
The period of revolution of a planet around the sun is the time it takes for the planet to complete one orbit of the sun. The period, P years, is give by Kepler's third law P^2=D^3, where D is the average distance from the sun in astronomical … 
Chemistry
The velocity of light is 1.86 × 108 mi/hr. The distance of Mercury from the Sun is approximately 5.78 × 107 km. How many minutes will it take for light from the Sun to travel to Mercury? 
physics
The sun is 1.5 1011 m from the earth. (a) Over what surface area is solar radiation spread at this distance? 
Phyics Toughest question on earth
Estimate the time difference between the longest day and the shortest day of a year in seconds if you lived on the Earth's equator with the assumptions below. Note: this is not the difference between solstices as we are adjusting the … 
heeeeeeeeeeeelp physics vrey tough
Estimate the time difference between the longest day and the shortest day of a year in seconds if you lived on the Earth's equator with the assumptions below. Note: this is not the difference between solstices as we are adjusting the … 
heeeeeeeeeeeelp physics
Estimate the time difference between the longest day and the shortest day of a year in seconds if you lived on the Earth's equator with the assumptions below. Note: this is not the difference between solstices as we are adjusting the … 
Math
Mercury's average distance from the sun is 57,910,000 km. The Earth is approximately 93,000,000 miles from the sun What would be the distance of a trip from Mercury to Earth, via the Sun. Look out for the units!!! (1 km =(0.62mi) Use … 
Physics
What is the average linear speed of Mercury about the Sun? 
Science
What distance was used to define the astronomical unit (AU) A. the average distance across the sun, its diameter B. the average distance from the sun to mercury, the closest planet C. the average distance from the sun to earth, our …