A head on elastic collision is a type of collision between two objects in which both objects have the same mass and speed, but are traveling in opposite directions. The collision is considered elastic because the kinetic energy and momentum of the objects are conserved.
Unlike inelastic collisions, which result in a loss of kinetic energy, elastic collisions are characterized by a conservation of kinetic energy and momentum. This means that after a head on elastic collision, the objects involved will continue to move, with no loss of energy.
Momentum is conserved in a head on elastic collision because the total momentum of the system before and after the collision remains the same. This is due to the fact that the objects involved have equal mass and opposite velocities, resulting in a zero net momentum before and after the collision.
The formula for calculating the velocities after a head on elastic collision is: v1 = (m1 - m2)v1i / (m1 + m2) and v2 = 2m1v1i / (m1 + m2), where v1i is the initial velocity of the first object and m1 and m2 are the masses of the two objects.
There are many real-life examples of head on elastic collisions, such as a game of pool, where the balls collide with each other and bounce off in opposite directions with no loss of energy. Another example is a game of billiards, where the cue ball collides with the other balls on the table, causing them to move in different directions with no loss of energy. Another example is two cars colliding head on, where the kinetic energy and momentum of the cars are conserved, resulting in a zero net momentum after the collision.