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## Homework Statement

Imagine a regular Newtons cradle (google it). The problem gives a the following information.

All the spherical ball have the same mass. Ball 1, m_1 is initially raised at height H_i.

A) Consider a stack consisting of just two balls. Let the speed of the first ball just before the collision be V_o. Solve V_f in terms of H. Solve for V_0 in terms of H.

**ANS**: Using the conservation of energy equation I got H = 0.5V_f^2 / g.

B) Just after the collision , the first ball bounces back at speed V_1, and the second ball moves forward at speed V_2. State the law of conservation of momentum for the general cases of masses m_1 and m_2 in terms of speed V_1 , V_2, and V_f ?

not sure what this is asking. Is is just m_1*V_1 + m_2*V_2 = m_1*V_1f + m_1 * V_1f

C) State the law of conservation of energy for elastic collision for the general case of masses m_1 and m_2 in terms of speed V_1, V_2, and V_f?

Is it just 1/2(m_1*V_1 + m_2*V_2) = (m_1*V_1f + m_1 * V_1f) 1/2

D) Solve for the speeds V_1 and V_2 for the special case that m = m, and m_2 = 2 M using the equations from part b and c above. Show that your solution satisfies the conservation of momentum and energy during the collision.

NEED HELP ON THIS PART!!!

E) To What height,H_1 will the first mass rebound after the elastic collision? To what maximum height, H_2, will the second mass rise before falling back.

Intuitively , H_1 rebounds to height 0.

And not sure about the next part.