A 4.5 kg object with a speed of 4.0 m/s collides head-on with a 11 kg object moving toward it with a speed of 3.0 m/s. The 11 kg object stops dead after the collision.(adsbygoogle = window.adsbygoogle || []).push({});

(a) What is the final speed of the 4.5 kg object?

(b) Is the collision elastic?

so i tried initial momentum = final momentum but I get the wrong answer.

(4.5 kg)(4.0 m/s) + (11 kg)(3.0 m/s)=(4.5 kg)(Vf)

and solving for Vf = 11.333 m/s, but that is the wrong answer.

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# Homework Help: Head on collision

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