Can someone check my work please, thank you.

AI Thread Summary
The discussion centers on a physics problem involving two hockey players colliding and locking skates. The user calculates the resultant velocity of the pair using conservation of momentum but finds their answer of 8.5 m/s [N15°E] differs from the textbook's 8.3 m/s [N16°E]. They express uncertainty about the discrepancy, suspecting a potential error in the textbook. Other participants confirm the user's calculations and suggest the textbook may be incorrect. The conversation concludes with a light-hearted acknowledgment of the situation.
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Can someone check my work please, thank you. :)

Homework Statement



A hockey player of mass 85 kg traveling at 15 m/s [N] collides with another hockey player of mass 70 kg at 5.0 m/s [E]. If the two hockey players lock skates during the collision and are held together, find the resultant velocity of the pair. Assume there is no friction.

Homework Equations



Ʃinitialρ = Ʃfinalρ

3. Solution, I feel like it is wrong because my answer is 0.2 off what it is in the textbook, I have no idea what decimal place they took. :(

(70) * (5) = (155) (v * cosθ)

(85) * (15) = 155(v * sinθ)

---------------------------

350 = (155) (v * cosθ)

1275 = 155(v * sinθ)

------------------

sqrt((350)^2 + (1275)^2) ≈ 1322.17

1322.17 / 155 ≈ 8.5 m/s [N15°E]

The answer in the textbook is 8.3 m/s [N16°E]

Someone check if I'm correct please. Thank you. :)<3
 
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PhanthomJay said:
I get your answer.

Yay! :)

Textbook's wrong again. xD
 
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