The gravitational pull from the sun and planets keep the planets going in a circular movements and not running into each other. The gravitational pull from the sun and planets which is causing them not to bump into each other. Hope this helps!
If you look carefully at the world, you will notice that there are many examples of physical and chemical weathering all around us.
Physical weathering occurs when rocks are broken apart without them changing their chemical composition. An example would be how, during the winter, ice can grow in cracks of rocks, weakening and eventually breaking them apart.
On the other hand, chemical weathering refers to rain water reacting with the mineral grains in rocks in order to form new minerals. An example of this would be how metal objects sometimes rust if they are left in the rain constantly.