Learning Materials
Features
Discover
Chapter 26: Q. 55 (page 740)
Find expressions for the equivalent capacitance of
(a) identical capacitors in parallel and
(b) identical capacitors in series.
(a) In parallel, the expression for the equivalent capacitance is.
(b) In series, the expression for the equivalent capacitance is .
Over 30 million students worldwide already upgrade their learning with Vaia!
All the tools & learning materials you need for study success - in one app.
Get started for free
The electric potential is at point A near a uniformly charged sphere. At point B, farther away from the sphere, the potential has decreased by 0.16 mV. How far is point A from the center of the sphere?
Consider a uniformly charged sphere of radius R and total cAlC charge Q. The electric field outside the sphere is simply that of a point charge Q. In Chapter 24, we used Gauss's law to find that the electric field inside the sphere is radially outward with field strength
a. The electric potential outside the sphere is that of a point charge Q. Find an expression for the electric potentialat position r inside the sphere. As a reference, let at the surface of the sphere.
b. What is the ratio
c. Graph V versus r for 0 r 3 R.
A nerve cell in its resting state has a membrane potential of , meaning that the potential inside the cell is less than the potential outside due to a layer of negative charge on the inner surface of the cell wall and a layer of positive charge on the outer surface. This effectively makes the cell wall a charged capacitor. When the nerve cell fires, sodium ions,, flood through the cell wall to briefly switch the membrane potential to . Model the central body of a nerve cell-the soma-as a diameter sphere with a -thick cell wall whose dielectric constant is 9.0. Because a cell's diameter is much larger than the wall thickness, it is reasonable to ignore the curvature of the cell and think of it as a parallel-plate capacitor. How many sodium ions enter the cell as it fires?
To what potential should you charge a capacitor to store of energy ?
Determine the magnitude and direction of the electric field at points 1 and 2 in Figure EX26.10.
What do you think about this solution?
We value your feedback to improve our textbook solutions.
Explanations 
Textbooks 
Exams 
GCSE 
IGCSE 
AS 
A Level 
International A Level 
University Admissions Tests 
Flashcards 
Vaia AI 
Notes 
Study Plans 
Study Sets 
Find a job 
Find a degree 
Student Deals 
Magazine 
Mobile App