Learning Materials
Features
Discover
Chapter 14: Q27P (page 580)
You rub a plastic comb through your hair and it now carries a charge of . What is the charge on your hair?
Over 30 million students worldwide already upgrade their learning with 91影视!
All the tools & learning materials you need for study success - in one app.
Get started for free
8 (a) An object can be both charged and polarized. On a negatively charged metal ball, the charge is spread uniformly all over the surface (Figure 14.42). If a positive charge is brought near, the charged ball will polarize. If any of the following quantities is zero, state this explicitly. (1) Draw the approximate final charge distribution on the ball. (2) At the center, draw the electric field due to the external positive charge. (3) At the center, draw the electric field due to the charge on the surface of the ball. (4) At the center, draw the net electric field.
(b) Next, consider a negatively charged plastic pen that is brought near a neutral solid metal cylinder (Figure 14.43). If any of the following quantities is zero, state this explicitly. (1) Show the approximate charge distribution for the metal cylinder. (2) Draw a vector representing the net force exerted by the pen on the metal cylinder, and explain your force vector briefly but completely, including all relevant interactions. (3) At the center, draw the electric field due to the external negative charge. (4) At the center, draw the electric field due to the charge on the surface of the ball. (5) At the center, draw the net electric field.
(c) Replace the solid metal cylinder with a solid plastic cylinder. (1) Show the approximate charge distribution for the plastic cylinder. (2) Draw a vector representing the net force exerted by the pen on the plastic cylinder. (3) Explain your force vector briefly but completely, including all relevant interactions.
Which statements about a neutral atom are correct? Select all that apply. (1) A neutral atom is composed of positively and negatively charged particles. (2) The positively charged particles in the nucleus are positrons. (3) The electrons are attracted to the positively charged nucleus. (4) Positively charged protons are located in the tiny, massive nucleus. (5) The radius of the electron cloud is twice as large as the radius of the nucleus. (6) The negatively charged electrons are spread out in a "cloud" around the nucleus.
A positively charged sphere is placed near a neutral block of nickel, as shown in Figure 14.92. (a) Which of the diagrams in Figure 14.93 best represents the equilibrium distribution of charge on the neutral nickel block?
(b) At location P inside the nickel block the electric field due to the charged sphere is . At equilibrium, which of the following statements must be true? (1) It is not possible to determine the electric field at location P due only to charges on the surface of the nickel block. (2) The electric field at location P due only to charges on the surface of the nickel block is . (3) Because the net electric field at location P is , the field at P due only to charges on the surface of the polarized nickel block must be .
: A thin, hollow spherical plastic shell of radius \({\bf{R}}\)carries a uniformly distributed negative charge \({\bf{ - Q}}\). A slice through the plastic shell is shown in Figure 14.95. To the left of the spherical shell are four charges packed closely together as shown (the distance \({\bf{s}}\) is shown greatly enlarged for clarity). The distance from the center of the four charges to the center of the plastic shell is \({\bf{L}}\) , which is much larger than \({\bf{s}}\left( {{\bf{L}} \gg {\bf{s}}} \right)\). Remember that a uniformly charged sphere makes an electric field as though all the charge were concentrated at the center of the sphere.
(a)Calculate the \({\bf{x}}\) and \({\bf{y}}\) components of the electric field at location B, a distance \({\bf{b}}\) to the right of the outer surface of the plastic shell. Explain briefly, including showing the electric field on a diagram. Your results should not contain any symbols other than the given quantities \({\bf{R,Q,q,s,L}}\), and \({\bf{b}}\)(and fundamental constants). You need not simplify the final algebraic results except for taking into account the fact that \({\bf{L}} \gg {\bf{s}}\).
(b)What simplifying assumption did you have to make in part (a)?
(c)The plastic shell is removed and replaced by an uncharged metal ball, as in Figure 14.96. At location Ainside the metal ball, a distance \({\bf{b}}\)to the left of the outer surface of the ball, accurately draw and label the electric field\({{\bf{\vec E}}_{{\bf{ball}}}}\) due to the ball charges and the electric field \({{\bf{\vec E}}_{\bf{4}}}\) of the four charges. Explain briefly.
(d)Show the distribution of ball charges.
(e)Calculate the \({\bf{x}}\) and \({\bf{y}}\) components of the net electric field at location A.
A small glass ball is rubbed all over with a small silk cloth and acquires a charge of +5nC. The silk cloth and the glass ball are placed 30 cm apart.
(a) On a diagram like that shown in Figure 14.71, draw the electric field vectors qualitatively at the locations marked 脳. Pay careful attention to directions and to relative magnitudes. Use dashed lines to explain your reasoning graphically, and draw the final electric field vectors with solid lines.
(b) Next, a neutral block of copper is placed between the silk and the glass.
On a diagram like that shown in Figure 14.72, carefully show the approximate charge distribution for the copper block and the electric field vectors inside the copper at the locations marked 脳.
(c) The copper block is replaced by a neutral block of plastic. Carefully show the approximate molecular polarization of the plastic block at the locations marked 脳 in Figure 14.73.
(d) Even if you have to state your result as an inequality, make as quantitative a statement as you can about the electric field at the location of the glass ball and the net force on the ball when the plastic block is in place compared to when there is no block. Explain briefly.
What do you think about this solution?
We value your feedback to improve our textbook solutions.
Explanations 
Textbooks 
Flashcards 
91影视 AI 
Notes 
Study Plans 
Study Sets 
Find a degree 
Magazine