# Explain me Prateek Sir.

Dear Student ,

The law of conservation of momentum states that: | |

"when some bodies constituting an isolated system act upon one another, the total momentum of the system remains constant." OR "the total momentum of an isolated system of interacting bodies remains constant." OR "Total momentum of an isolated system before collision is always equal to total momentum after collision." | |

Consider an isolated system of two bodies 'A' and 'B' as shown. The masses of bodies are ma and mb and | |

MATHEMATICAL REPRESENTATION | |

Consider two bodies of mass m_{1} and m_{2} moving initially with velocities u_{1} and u_{2}. | |

| |

Total momentum before collision = m_{1}u_{1} + m_{2}u_{2} | |

| |

Let after collision their velocities become v_{1} and v_{2}. | |

| |

Total momentum after collision = m_{1}v_{1} + m_{2}v_{2} | |

According to the law of conservation of momentum | |

m_{1}u_{1} + m_{2}u_{2} = m_{1}v_{1} + m_{2}v_{2} |

Regards

**
**