“The total momentum of an isolated system always remains constant”
Conservation of momentum states that the total momentum of a closed system remains constant, unless acted upon by an external force. This means that if two or more objects interact, the total momentum before the interaction will be equal to the total momentum after the interaction. This principle is useful in many fields, including physics, engineering, and sports, to understand and predict motion and changes in motion.
For simplicity consider a system of two billiard balls of mass m1
and m2 moving in straight line with velocities U1 and U2
respectively where U2 is greater than U1
Total momentum before collision = m1U1 + m2U2
After collision the velocities become v1 and v2 respectively,
Total momentum after collision = m1v1 + m2v2
According to law of conservation of momentum:
(total momentum before collision) = (total momentum after collision)
m1U1 + m2U2 = m1v1 + m2v2