Given in this page is the formula for finding the magnitude of the total initial momentum of the two block system based on the velocity and mass of the block1 and block2. As per the Magnitude of the total initial momentum of the two block system formula, total initial momentum can be calculated by summing the products of mass and velocity of block1, and the mass and velocity of block2. Just substitute the values in the formula and do the operations as guided by the formula to get the answer.
The Total Initial Momentum of an object is also connected with the Newton's third law, and according to it the total momentum of a system of interacting objects is conserved, when not acted on by external forces. Refer this Magnitude of the total initial momentum of the two block system formula to do the total initial momentum calculation on your own.
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