Question

state and explain the principle of conservation of linear momentum

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Answer 1

Answer:

The principle of conservation of momentum states that if the two objects collide, then total momentum before and after the collision will be the same if there is no external force acting on the colliding objects.!

Explanation:

Answer 2

Answer:

The principle of conservation of momentum states that the total momentum of a system of colliding objects remains constant provided no resultant external force acts on the system.

Consider an isolated system of two objects m1 and m2 whereby m1 is striking m2. (An isolated system is one which has no external forces acting on it.)

Mathematically, we can deduce the principle of conservation of linear momentum by applying Newton’s second and third laws to the colliding bodies as illustrated below:

From Newton’s third law, the contact forces of impact are action and reaction pair

F21 = – F12

If the two bodies are in contact for a time of Δt,

F21 Δt = – F12 Δt ——(1)

impulse on m1 = F21 Δt (Recall that impulse = change in momentum)

F12 Δt = m1v1 – m1u1

impulse on m2 = F12?t

F21 Δt = m2v2 – m2u2

Substitute into (1),

(m1v1– m1u1) = – (m2v2 – m2u2)

Rearranging => m1u1 + m2u2 = m1v1 + m2v2

Thus, total linear momentum before collision = total linear momentum after collision,

which proves the principle of conservation of linear momentum.

Explanation: