Forces in Two Dimensions

• How do we analyze forces in 2-Dimensions?                                                                         We can analyze forces in two dimensions by analyzing each dimension separately. We use the x or horizontal dimension and the y or vertical dimension. In order to analyze the dimensions separately, we can use trigonometry. We use fx= F cos theta and fy= f sin theta. You get the net force for each dimension when you add the vertical and hortizontal components separately. 
• How do forces cause objects to move in a circle?                                                   Centripetal force is any force that causes and object to move in a circular motion. The centripetal force is a center-pointing net force, which causes the object to move in a circle. The object can move at constant speed, but it is constantly changing direction. 
• What does it mean to be in orbit? How do satellites orbit planets? How do planets orbit the sun?                                                                                                                                           To be in orbit means that one object is on a continuous elliptical path around another object in space. Satellites orbit planets because an object will stay in motion unless and unbalance force acts on it. The force of gravity pulls the satellite towards the earth. The satellite is actually falling around the earth because as the earth curves, the satellite curves. It must be in orbital velocity. Planets orbit the sun because of the centripetal force of gravity that comes from the sun. There is no other force in the solar system to keep them from orbiting. The earth orbits at a constant speed, but it is accelerating because the direction of it's velocity is constantly changing.