Question

A particle leaves the origin with an initial velocity v=(2.40 m/s)x hat and moves with a constant acceleration a=(-1.90 m/s ^2)x hat+(3.20 m/s ^2)y hat. How far does the particle move in the x direction before turning around? Answer is 1.48 m. What is the particle's velocity at this time? I can't figure this second part out.

Answer 1

When a particle is turning around in some direction (x in this case), its velocity compnent in that direction is zero.