Learning Materials
Features
Discover
Chapter 25: Q. 40 (page 711)
A -3.0 nC charge is on the x-axis at x = -9 cm and a +4.0 nC
charge is on the x-axis at x = 16 cm. At what point or points on
the y-axis is the electric potential zero?
The points on y-axis where the potential of electric is zero are
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
A disk with a hole has inner radius Rin and outer radius Rout.The disk is uniformly charged with total charge Q. Find an expression for the on-axis electric potential at distance z from the center of the disk. Verify that your expression has the correct behavior when RinS0.
Two small metal cubes with masses 2.0 g and 4.0 g are tied together by a 5.0-cm-long massless string and are at rest on a frictionless surface. Each is charged to +2.0 mC. a. What is the energy of this system? b. What is the tension in the string? c. The string is cut. What is the speed of each cube when they are far apart?
Three electrons form an equilateral triangle with 1.0 nm on each side. A proton is at the center of the triangle. What is the potential energy of this group of charges?
Living cells “pump” singly ionized sodium ions, Na+, from the inside of the cell to the outside to maintain a membrane potential ∆Vmembrane = Vin - Vout = - 70 mV. It is called pumping because work must be done to move a positive ion from the negative inside of the cell to the positive outside, and it must go on continuously because sodium ions “leak” back through the cell wall by diffusion. a. How much work must be done to move one sodium ion from the inside of the cell to the outside? b. At rest, the human body uses energy at the rate of approximately 100 W to maintain basic metabolic functions. It has been estimated that 20% of this energy is used to operate the sodium pumps of the body. Estimate—to one significant figure—the number of sodium ions pumped per second.
A proton is fired from far away toward the nucleus of an iron atom. Iron is element number , and the diameter of the nucleus is . What initial speed does the proton need to just reach the surface of the nucleus? Assume the nucleus remains at rest.
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