Q.State the law of conservation of linear momentum. It is a consequence of which law? Give an example from our daily life for conservation of momentum. Does it hold good during burst of a cracker?

[!TLDR] 'The total momentum of an isolated system is conserved during any interaction' -- a direct consequence of Newton's third law (equal-and-opposite internal forces). Example: recoil of a gun on firing. Yes, it holds for a cracker's burst too. [!ANSWER] Total momentum of …

The law of conservation of linear momentum states: 'The total momentum of an isolated system is conserved during any interaction' (4.7) -- equivalently, if the net EXTERNAL force on a system is zero, its total momentum $\vec{p}=\sum m_i\vec{v_i}$ remains constant, even though individual particles' momenta may change due to internal forces. It is a direct CONSEQUENCE of Newton's THIRD LAW: internal forces between any two parts of the system always occur in equal-and-opposite action-reaction pairs, so their contributions to the total rate of change of momentum, when summed over the whole system, always cancel exactly, leaving only external forces able to change the system's total momentum. Daily-life example: a GUN recoiling backward when a bullet is fired forward -- before firing, the gun-bullet system has zero total momentum; after firing, the forward momentum of the bullet is exactly balanced by the backward momentum (recoil) of the gun, keeping the vector sum at zero, since the explosive gases exert only INTERNAL forces on the gun-bullet system. Yes, this holds equally well during the burst of a firecracker/cracker: before bursting, the (stationary) cracker has zero momentum; after exploding into many fragments flying off in different directions, the VECTOR SUM of all the fragments' momenta is still exactly zero, …

State the law, derive it conceptually from Newton's third law (internal forces cancelling pairwise), and apply it to a famil …

Forgetting momentum conservation is a VECTOR statement -- the fragments of a cracker fly off in many directions with large individual moment …