Afreight car moves along a frictionless level railroad track at constant speed. the freight car is open on the top. a large load of sand is suddenly dumped into the freight car. what happens to the speed of the freight car?

An ideal transformer has 60 turns in its primary coil and 360 turns in its secondary coil. if the input rms voltage for the 60-turn coil is 120 v, what is the output rms voltage of the secondary coil?

Afixed electric space heater wired by a cable with an ampacity of 30 a should draw a maximum current of a. 30 a. b. 24 a. c. 15 a. d. 27 a.

Intro: a solid ball of radius rb has a uniform charge density ρ. part a: what is the magnitude of the electric field e(r) at a distance r> rb from the center of the ball? express your answer in terms of ρ, rb, r, and ϵ0. part b: what is the magnitude of the electric field e(r) at a distance r express your answer in terms of ρ, rb, r, and ϵ0. part c: let e(r) represent the electric field due to the charged ball throughout all of space. which of the following statements about the electric field are true? check all that apply. e(0) = 0 e(rb)=0 limr→∞e(r)=0 the maximum electric field occurs when r=0 the maximum electric field occurs when r=rb the maximum electric field occurs as r→∞.