Calculating Charge Distribution in a Parallel Plate Capacitor

Click For Summary
SUMMARY

The discussion focuses on calculating the charge distribution in a parallel plate capacitor using a suspended charged ball. The ball, with a mass of 6.95×10-3 kg and a charge of +0.11 mC, is in equilibrium at a 30.0° angle between the plates. The electric field (E) is calculated using the formula E = Q/(ε0A), where A is the area of the plates (0.0152 m2). The mechanical equilibrium of the ball is expressed as T + G + Fel = 0, where G = mg and Fel = qE.

PREREQUISITES
  • Understanding of electric fields and forces
  • Familiarity with the concepts of mechanical equilibrium
  • Knowledge of the formula for electric field in capacitors: E = Q/(ε0A)
  • Basic vector analysis for resolving forces
NEXT STEPS
  • Study the derivation and applications of the electric field formula E = Q/(ε0A)
  • Learn about mechanical equilibrium in physics, focusing on tension and gravitational forces
  • Explore the concept of charge distribution in capacitors and its implications in circuit design
  • Investigate the role of angles in force resolution and vector analysis in physics problems
USEFUL FOR

Physics students, electrical engineers, and anyone interested in understanding charge distribution and electric fields in capacitors.

figs
Messages
27
Reaction score
0
A small plastic ball of mass 6.95×10-3 kg and charge +0.11 mC is suspended from an insulating thread and hangs between the plates of a capacitor. The ball is in equilibrium, with the thread making an angle of 30.0° with respect to the vertical. The area of each plate is 0.0152 m2. What is the magnitude of the charge on each plate? (the picture shows the positive plate on the left, the ball leaning 30 deg toward the negative plate, and the negative plate on the right.

With this problem, I solved for E using E=(q)/(AEo). I don't know where to go from here though. I'm confused.
 
Last edited:
Physics news on Phys.org
Write the mechanical equilibrium of the ball
[tex]\vec{T}+\vec{G}+\vec{F_{el}}=0[/tex]
onto the horizontal and vertical direction. You now that
[tex]G=mg[/tex]
[tex]F_{el}=qE[/tex]

and [tex]E=\frac{Q}{\epsilon_0 A}[/tex]

...
 
Last edited:
oooo, i set up my vectors wrong in the beginning!
how silly of me, thank you very much for the help.
 

Similar threads

  • · Replies 18 ·
Replies
18
Views
3K
Replies
11
Views
4K
  • · Replies 20 ·
Replies
20
Views
4K
  • · Replies 6 ·
Replies
6
Views
3K
Replies
3
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
Replies
1
Views
1K
  • · Replies 20 ·
Replies
20
Views
4K
Replies
3
Views
9K
  • · Replies 2 ·
Replies
2
Views
2K