-- 6.5 m/s The negative sign for the final velocity means that the ball is moving
downward (the negative direction) at 1.5 s.
Practice Problems
20. Concept Check The velocity-time equation for a golf cart is
vp = (1 m/s) + (-0.5 m/s?)t
(a) What is the cart's initial velocity?
(b) What is the cart's acceleration?
21
nd has

Athin nonconducting rod with a uniform distribution of positive charge q is bent into a circle of radius r. the central perpendicular axis through the ring is a z-axis, with the origin at the center of the ring. a) what is the magnitude of the electric field due to the rod at z = 0? n/c (b) what is the magnitude of the electric field due to the rod at z = infinity? n/c (c) in terms of r, at what positive value of z is that magnitude maximum? r (d) if r = 4.00 cm and q = 9.00 µc, what is the maximum magnitude? n/c