What do wind turbines, hydroelectric dams, and ethanol plants have in common

Ababy stroller is a rest on top of a hill which is 10 m high. the stroller and baby have a mass of 20 kg. what is the potential energy of the baby and stroller?

What does the law of conservation of mass state?

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