Trini has finished preschool for the day and her dad has come with a surprise. He has tied a 1.80 m rope to a cart to give her a spin in the cart (during which the rope is parallel to the ground). Together, Trini and the cart have a combined mass of 24 kg. Trini's 2 kg backpack is behind her in the cart. The friction between the wheels of the cart and the ground is negligible.

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