Solving 2D Velocity at Point P on a Rigid Body - HELP ME!

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The discussion centers on calculating the velocity at a point on a rigid body in 2D using a specific equation. The equation incorporates the linear velocity of the center of mass, angular velocity, and the perpendicular distance vector from the center of mass to the point in question. The poster initially arrives at a seemingly unrealistic velocity result for a point on the body, prompting confusion. Upon further examination, it is revealed that the angular velocity should be in radians, which clarifies the calculations. The conversation highlights the importance of unit consistency in physics calculations, particularly when dealing with angular and linear velocities.
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Hi. I think this is my 1st post here but I browse a lot on the forum :smile:
I was trying to know the velocity at a point on a rigid Body (in 2D) and i found this equation on a paper:
http://members.fortunecity.de/porquilho/eqVel.jpg
where:
Vap = velocity at point P (body A)
Va1 = Linear Velocity of the Rigid Body CM (m/s)
w1 = Angular Velocity of the Rigid Body (rad/s)
rap with a invers "T" = the perpendicular distance vector from the CM to point p.

Im working on 2 dimension here so angular velocity is just a scalar

The question i have is the unreal result that this equation gives to me, for exemple:
Va1(0, -5)
w1=1.5;
rap(-5,-20) -> now we take the prependicular vector (90º to the left)
rapT(20, -5);
and if I am not mistak making the calculations
Vap = (0,-5) + ( 1.5*20 + 1.5*(-5))
Vap = (0,-5) + ( 30+(-7.5))
Vap = (0,-5) + 22.5 = (22.5, 17.5);
Vap=(22.5, 17.5)

I think this value is too high, are my calculations wrongs ?
HELP ME
 
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Why is that "unreal"? This object is not moving very fast in translation but it is spinning like heck and it's pretty darn big.
 
maybe ur right

well now that i look better the angular velocity is in rad's!
lool forgot that
Thanks.
 
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