If the magnitude of the net force acting on the particle is F , how long does it take the particle to acquire its final velocity, 2v in the positive y direction? Express your answer in terms of m, F and v If you use a numerical coefficient, use three significant figures. I found that the answer is (mv/F) but its asking with use three significant figures so how i can find it

Consider a uniformly charged ring in the xy plane, centered at the origin. the ring has radius a and positive charge qdistributed evenly along its circumference. a)what is the direction of the electric field at any point on the z axis? . b)what is the magnitude of the electric field along the positive z axis? use k in your answer, where k=14πϵ0. d)the ball will oscillate along the z axis between z=d and z=−d in simple harmonic motion. what will be the angular frequency ω of these oscillations? use the approximation d≪a to simplify your calculation; that is, assume that d2+a2≈a2. express your answer in terms of given charges, dimensions, and constants