Direction Cosines are the Cosines Of the Angles of the angles between and the line and the coordinate Axis. If we have a vector (a,b,c) in space then two a=x2-x1,b=y2-y1 and c =z2-z1 are called the direction...
There are 3 Types of Collisions Elastic, Inelastic and Totally Inelastic collision. Momentum is conserved in all these three types ( No external force is involved, so the system is called a Closed System....