...sorry for doing this, but having trouble with some problems(adsbygoogle = window.adsbygoogle || []).push({});

1) A particle starts from rest at t=0 at the origin and moves in the xy plane with a constant acceleration of a= (2i + 4j) m/s2. After a time t has elaped, determine (a) the x and y components of velocity. (b) the coordinates of the particle, and (c) the speed of the particle.

I get a) Vx= (2t)m/s and Vy=(4t)m/s, but not the rest...

and...

2) A ball swings in a vertical circle at the end of a rope 1.5 M long. When it is 36.9* past the lowest point on its way up, the ball's total acceleration is (-22.5i + 20.2j) m/s2. For that instant, a) determine the magnitude of its centripetal acceleration, and b) determine the magnitude and direction of its velocity.

I know that v^2/R= Ac, but i don't know how to get the velocity:(

Any help will be appreciated

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# Homework Help: Motion in 2d/Centripetal Acceleration

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