Momentum, elastically collisino, velocity

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The discussion focuses on a physics problem involving a pendulum and an elastic collision. A 0.200-kg mass swings down from a horizontal position and collides with a stationary 0.400-kg mass on a frictionless surface. The initial velocity of the pendulum mass at the bottom of the swing is calculated using conservation of energy, resulting in 3.96 m/s. The conservation of momentum and energy equations are then applied to determine the final velocities of both masses after the collision, yielding -1.32 m/s for the 0.200-kg mass and 2.64 m/s for the 0.400-kg mass. The discussion emphasizes the importance of using these fundamental principles to solve the problem effectively.
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Homework Statement



A 0.200-kg mass is attached of a 0.800 m length string to form a pendulum. The pendulum is released from a horizontal position. At the bottom of its swing, it collides elastically with a 0.400-kg mass which is at rest on a horizontal, frictionless v surface. Find the velocity of each mass immidately after the collision.


Homework Equations


p=mv
v1+v1f=v2+v2f


The Attempt at a Solution


the answers are
v .2kg= -1.32m/s
v .4kg= 2.64m/s

but I need to know the steps so I can study for the tests.
 
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When the mass is released from its initial position, what is its velocity at the bottom of the swing? (Use the conservation of energy to find this.) Then use the conservation of momentum and energy to find the velocities.
 
bottom of swing velocity = 3.96m/s(if I did right)
(3.96)(.2)=.2(x)+.4(y)

x y are the velocities, not sure how to do next now.
 
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J'étais à la banque quand
J'avais peur des chiens
 
Use law of conservation of energy.
1/2*m1v1i^2 = 1/2*m1*Vf1^2 + 1/2*m2*v2f^2-------(1)
According to conservation of momentum
m1v1i = m1v1f + m2v2f-----------(2)
From these two equations find v1f and v2f.
 
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