An applied force is a force that is applied to an object by a person or another object. Example: pushing a box to the other side of a room.
A normal force is a force that surfaces exert to prevent solid objects from passing through each other. Example: resting a book upon a table.
Drag is a force acting opposite to the relative motion of any object moving with respect to a surrounding fluid. This doesn't really match the force we use.
However, an attractive force is a force by which one object attracts another. Example: two magnets pulling/colliding together. This is a good example of a force we exert on objects when it is pulled toward us.
Section 3.2Primary Structure: Amino Acids Are Linked by Peptide Bonds to Form Polypeptide Chains. Proteins are linear polymers formed by linking the α-carboxyl group of one amino acid to the α-amino group of another amino acid with a peptide bond (also called an amide bond).
