# Homework Help: Universal gravity

1. Sep 17, 2008

### hoooossein

hey i have 2 very simple questions i cant seem to do.

1) determine the speed of the earth around the sun...

2)The asteroid Pallas has an orbital period of 4.62 years. find the semi-major axis of its orbit.

i no these r simple but i jsut cant seem to get them can someone help me or let me know of some formulas that will help? thank you in advance

2. Sep 17, 2008

### hage567

Look up Kepler's laws in your book.