Ok... This one is bugging me...

(+) - Proton

Ok, so we need to find the Velocity for W and V as shown in the image...

u=100m.s<sup>-1</sup>

Here is what I did:

if u = 100m.s<sup>-1</sup> with the angles 30Â° and 60Â° the collision is elastic because the angle between the two objects is 90Â°.

Wx/W = Cos(60)

Wx = W.Cos(60)

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X-Dir

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∑<sub>p before</sub> = ∑<sub>p after</sub>

m<sub>1</sub>V<sub>1</sub>+m<sub>2</sub>V<sub>2</sub> = m<sub>1</sub>V<sub>1</sub>+m<sub>2</sub>V<sub>2</sub>

(Ã·m) 100 = W.cos(60) + V.cos(30)

(1) 200 = W + √(3).V

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Y-Dir

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∑<sub>p before</sub> = ∑<sub>p after</sub>

m<sub>1</sub>V<sub>1</sub>+m<sub>2</sub>V<sub>2</sub> = m<sub>1</sub>V<sub>1</sub>+m<sub>2</sub>V<sub>2</sub>

(Ã·m) 0 = W.sin(60) + V.sin(30)

(2) 0 = √(3).W + V

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(2) in (1)

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200=W+√(3).(√(3)W)

200=2W

W=100m.s<sup>-1</sup>

But thats not true. That says that the 1st one stands still and the 2nd one moves. That means that this is 1Dimentional... but its not...

I'm confused... Can anyone please help...

Thanks