A mass m moves at speed v along +x and sticks to a mass 3m moving at speed 2v along +y. Determine velocity of the combined mass.
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A mass m moves at speed v along +x and sticks to a mass 3m moving at speed 2v along +y. Determine velocity of the combined mass.

G1 Physics · Accepted Answer

Step 1 — Principle: Conserve momentum in a perfectly inelastic collision; objects share a common final velocity. Step 2 — Working: Vector momentum conservation: (4m)V=mv î+(3m)(2v)ĵ. Step 3 — Working: Thus V=(v/4)î+(6v/4)ĵ=(v/4)î+(3v/2)ĵ. Correct answer: A — (v/4)î+(3v/2)ĵ.