| A | B |
| orbit | the path of an object around another object |
| satellite | an object that revolves or moves around another object |
| air resistance | the opposition to motion caused by air particals |
| sliding friction | friction that results when solid surfaces slide across one another |
| weightlessness | a condition when there isn't any pull of gravity |
| velocity | the speed and direction is moving |
| ligament | something that holds bones together |
| synapse | a gap between nerve cells |
| cartilage | flexible bonelike substance |
| reflex | an automatic movement |
| force | a push or pull |