A block slides with constant velocity down a rough inclined plane that makes an angle of 0 with the horizontal . It experiences three forces : gravitational (fg) , normal (FN), and frictional (Ff) which of the following gives the magnitude of the net force on the block A) zero
B) Ff+Fn-Fg
C)Fgcos0-Ff
D)Fg sin0 + Fn cos0 -Ff

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