Forces in 2D

1. What does it mean to analyze forces in 2D?
2. How do forces cause objects to move in a circle?
3. What does it mean to be in orbit? How do satellites orbit planets? How do planets orbit the sun?

1. What does it mean to say we live in a 3-D universe? Well it means that there are 3 different dimensions in our world. There is a 2nd, 3rd, and 4th dimension. The 2nd and 3rd dimension have x-y components while the 4th dimension has 3-Dimensions of space and 1-Dimension of time(x, y, z, t). As a result, we can analyze these dimensions separately or independent of one another. 

2.Forces cause objects to move in a circle because they must feel a net force that always points to the center of the circular path. This is called the centripetal force. In order for this to work, a string tension pointing to the center point  must be present or else the object will travel in a straight line instead of going in a circle.

3.  To be in orbit means a path taken by an object as it circles another object. It's like how satellites orbit planets and how planets orbit the sun. With the help of the centripetal force, these satellites and planets orbit follow a path that help them move in this circular motion. It is important to understand that the gravitational force puling these objects to the center and as it moves at a constant speed happens because of the string tension that isn't being disturbed by any friction, causing it to go off in a straight line.