Collisions problem completed - is it correct?

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AI Thread Summary
The discussion centers on a physics problem involving a collision between two pucks with different masses and velocities. The calculations provided show that puck A, after the collision, has a speed of approximately 2.58 m/s, while puck B has a speed of about 1.94 m/s. The user expresses uncertainty about the correctness of their solution, but the calculations align with the principles of conservation of momentum. The final confirmation indicates that the answers are indeed correct. This resolution highlights the importance of verifying calculations in collision problems.
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Hello - I am pretty sure this is correct but there is no answer for me to check. My friend (who is a lot smarter than me :P ) got a different answer entirely. Is the following answers correct?

Homework Statement


Puck A has a mass of 0.0300 kg and is moving along the x-axis with a velocity of +4.20 m/s. It makes a collision with puck B, which has a mass of 0.0600 kg and is initially at rest. The collision is not head-on. After the collision, the two pucks fly apart with the angles shown in the drawing. Find the speed of (a) puck A and (b) puck B.

puck a is 65 degrees above x axis
puck b is 37 degrees below the x axis

The Attempt at a Solution



(0.0300) (4.2) + 0 = (0.0300) (VA COS 65) + .0600 (VB COS 37)
0.126 = 0.0127 VA + 0.0479VB

0 = 0.0300 (VA SIN 65) + (0.0600)(-VBSIN 37)
= 0.0272 VA + -0.0361 VB
0.0361VB = 0.0272VA
VB = 0.0272VA/0.0361
VB = 0.753 VA

0.126 = 0.0127 VA + 0.0479VB
0.126 = 0.0127 VA + (0.0479)(0.753)
0.126 = 0.0127 VA + 0.0361 VA
0.126 = 0.0488 VA
VA = 0.126/10.0488
VA = 2.58 m/s

VB = 2.58 m/s x 0.753
= 1.94m/s
 
Last edited:
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Your answer appears to be correct.
 
rl.bhat said:
Your answer appears to be correct.

Thank you very much - I appreciate it.
 
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