The nucleus of a 125xe atom (an isotope of the element xenon with mass 125 u) is 6.0 fm in diameter. it has 54 protons and charge q=+54e(1 fm = 1 femtometer = 1×10−15m.) hint: treat the spherical nucleus as a point charge.

a) what is the electric force on a proton 9.0 fm from the surface of the nucleus?

express your answer in newtons.

b) what is the proton's acceleration?

express your answer in meters per second squared.

2) two 3.5-cm-diameter disks face each other, 2.0 mm apart. they are charged to ± 11 nc .

a) what is the electric field strength between the disks?

express your answer in newtons per coulomb.

b) a proton is shot from the negative disk toward the positive disk. what launch speed must the proton have to just barely reach the positive disk?

You are the coordinator for a program that is going to take place at night in a rectangular amphitheater in the mountains. you will have no access to any electricity, but you must be able to illuminate the entire grounds. you know the intensity of the light from a lantern varies inversely as the square of the distance from the lantern. suppose the intensity is 90 when the distance is 5 m. a. write an equation to model the situation. b. solve for the constant of variation. c. write the equation to model the situation using the constant () of variation. d. you have been given lanterns with 40 light intensity. use your equation to solve for the distance from the lantern. e. you need to illuminate 225 km. how many meters do you need to light? f. how many lanterns will you need?