Solving Momentum Collision Problems

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The discussion revolves around solving a momentum collision problem involving two objects with different masses and velocities. The initial calculations for the velocities prior to the collision were based on the momentum conservation principle, but the user received incorrect answers. A key mistake identified was the misapplication of sine and cosine functions due to misunderstanding the angle's orientation, as 24 degrees east of north indicates a greater northward direction than eastward. Correcting this misunderstanding is crucial for accurately determining the initial velocities. The conversation emphasizes the importance of vector components in momentum calculations.
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[SOLVED] Momentum - collision

Homework Statement



An object of mass 950kg traveling east collides with an object of mass 1900kg traveling north. The two objects then move off together at 16m/s in a direction of 24degrees east of north. Find their respective velocities prior to the collision.

Homework Equations



p = mv

The Attempt at a Solution


Momentum after collision = 2850 x 16 = 45600
As momentum is a vector, then breaking it into its components we get:
Object 1: 950 x v1 = (45600)cos24 ... v1=43.85m/s
Object 2: 1900 x v2 = (45600)sin 24... v2=9.76m/s

I thought this seemed simple enough, but apparently the answers are wrong... can anyone see where I might have made mistake, or am I just going about it the wrong way altogether?
 
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Ginerva123 said:

Homework Statement



An object of mass 950kg traveling east collides with an object of mass 1900kg traveling north. The two objects then move off together at 16m/s in a direction of 24degrees east of north. Find their respective velocities prior to the collision.

Homework Equations



p = mv

The Attempt at a Solution


Momentum after collision = 2850 x 16 = 45600
As momentum is a vector, then breaking it into its components we get:
Object 1: 950 x v1 = (45600)cos24 ... v1=43.85m/s
Object 2: 1900 x v2 = (45600)sin 24... v2=9.76m/s

I thought this seemed simple enough, but apparently the answers are wrong... can anyone see where I might have made mistake, or am I just going about it the wrong way altogether?

you got the sin/cos mixed up... 24 degrees "east of north" is pointing more north than east...
 

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