The acceleration of a particle on a horizontal xy plane is given by a=3ti + 4tj, where a is in meters per second-squared and t is in sec. At t=0, the particle has the position vector r=(20.0m)i + (40.0m)j and the velocity vector(adsbygoogle = window.adsbygoogle || []).push({});

v=(5.00m/s)i +(2.00m/s)j. At t=4.00 s, what are its position vector in unit-vector notation and the angle between its direction of travel and the positive direction of the x axis?

I have no idea what to do at all:surprised https://www.physicsforums.com/images/smilies/surprised.gif [Broken]

:surprised

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# The acceleration of a particle on a horizontal xy plane

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