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2 years ago

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Two students, sitting on frictionless carts, push against each other. Both are initially at rest and the mass of student 1 and t

he cart is M, and that of student 2 and the cart is 1.5M. If student 1 pushes student 2 so that she recoils with velocity v,  what is the velocity of student 2.

1 answer:

Zepler [3.9K]2 years ago

6 0

Answer:

v₂ = v/1.5= 0.667 v

Explanation:

For this exercise we will use the conservation of the moment, for this we will define a system formed by the two students and the cars, for this isolated system the forces during the contact are internal, therefore the moment conserves.

Initial moment before pushing

p₀ = 0

Final moment after they have been pushed

$p_{f}$ = m₁ v₁ + m₂ v₂

p₀ = $p_{f}$

0 = m₁ v₁ + m₂ v₂

m₁ v₁ = - m₂ v₂

Let's replace

M (-v) = -1.5M v₂

v₂ = v / 1.5

v₂ = 0.667 v

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