(adsbygoogle = window.adsbygoogle || []).push({}); A submarine of mass 2.3 times 106 kg and initially at rest fires a torpedo of mass 260 kg. The torpedo has an initial speed of 100.9 m/s. What is the initial recoil speed of the submarine? Neglect the drag force of the water.

My work:

Pi=Pf

Pi=0

Pf= Mtorpedo * Vtorpedo - Msub * Vsub

Vsub = (260kg * (100.9 m/s) ) / 2.3 x 10^6

I get Vsub = .0114 m/s

Why is this wrong?? Thanks

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# Homework Help: Submarine and torpedo

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