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While 75-kg Anthony roller skates at 3 m/s, 60-kg Sue jumps into his arms with a velocity of 5 m/s. How fast does the pair go together?

Velocity: m/s

Direction:

User Klaujesi
by
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1 Answer

11 votes

Apply conservation of linear momentum


\\ \rm\Rrightarrow m1v1+m2v2=(m1+m2)V3


\\ \rm\Rrightarrow 75(3)+60(5)=(75+60)V3


\\ \rm\Rrightarrow 225+300=135v3


\\ \rm\Rrightarrow 525=135v3


\\ \rm\Rrightarrow V3=3.89m/s

User Tuntable
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