A54.0 kg ice skater spins about a vertical axis through her body with her arms horizontally outstretched, making 2.50 turns each second. the distance from one hand to the other is 1.5 m. biometric measurements indicate that each hand typically makes up about 1.25 % of body weight. part a)
what horizontal force must her wrist exert on her hand?
part b)
express the force in part (a) as a multiple of the weight of her hand.

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