The filament of a lightbulb has a resistance of r0=12ω at 20 ∘c and 140 ω when hot. part apart complete part b in this temperature range, what is the percentage change in resistance due to thermal expansion? express your answer using two significant figures. rexpansion−r0r0r e x p a n s i o n − r 0 r 0 = 1100 %

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→∞.