I have this earth science packet of 44 questions; can you help with the ones I'm

[Jen]

comfused on? 9) Two celestial objects are 10 light years away from eachother, What would happen to the force of gravitation between them if they were only 5 light years away? The gravitational attraction would -- increase or decrease?
10) If Mars and Earth were both placed at the same distance from the Sun, which planet will expirience a greater gravotational attraction to the sun? -- Earth or Mars.
26) What is the relationship between distance from the sun and the length of time for one orbit around the sun? 37) What is the name if the nuclear reaction that produces energy in stars? Its two words. Can you explain why these answers are what they are, because I don't understand them. ---------------------------------- I'm really not in the mood to hear people tell me I'm lazy; because out of 44 questions, 4 of them I need help with; so don't answer if thats what youre here to do. Thankyou!

[MVB]

increase by 4X. (gravitational force inversely proportional to the square of the distance)

Earth -- it's more massive

Kepler's Third Law: The squares of the orbital periods of planets are directly proportional to the cubes of the semi-major axes.

Nuclear fusion.

[Greg C]

9. Increase.
10.Probably mars because it is smaller.
26. If the earth were any closer to the sun it would orbit it faster.
37. Nuclear fusion.

[al_moskowitz]

I'm not going to say that in your case... It sounds like you're using Y!A for exaclty the purpose for which it was designed..

9) the gravity effects will increase... If you decrease the distance by 1/2 then gravity will increase by a factor of 4... (the inverse square law for gravity).

10) For all intents and purposes, they will both feel the exact same pull from the sun...

26) Google "Kepler's Law of Planetary Motion"

37) Hydrogen Fusion - Hydrogen atoms are slammed together (fused) forming Helium and converting some of the mass into energy...

Good luck with 26 - I know you can do it...