Calculating voltage from multiple point charges

AI Thread Summary
To calculate the electric potential from multiple point charges, the formula used is v = k(q1/r1 + q2/r2 + q3/r3). In this case, three point charges are positioned at different heights, with the goal of finding the potential at a height of 8 km. The user correctly converted distances from kilometers to meters and summed the contributions from each charge, arriving at a potential of 7.5E7 volts. The negative charge's effect was appropriately subtracted from the total potential. The calculations and approach taken are validated as correct.
Eric_meyers
Messages
64
Reaction score
0

Homework Statement


A point charge 10 km in the air with a charge of 40 coulombs
A point charge 5 km in the air with a charge of -40 coulombs
A point chare 2 km in the air with a charge of 10 coulombs
-Find the electric potential due to these charges at a point which at a height of 8 km and on the vertical line passing through the charges.


Homework Equations


kq1/r1 + kq2/r2


The Attempt at a Solution



So I summed them up

v = k (40C/2000m - 40C/3000m + 10C/6000m) = 7.5E7

My question is, is do I need to convert km to m and was I correct in subtracting the negative 40 coulomb charge from the rest of the positive charges?
 
Physics news on Phys.org
Yes and yes. Looks good to me.
 

Thread 'Rolling without slipping on a curved surface'

Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
View full post »

Thread 'Struggling to understand the concept of this question (ice cube in water optics question)'

TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
View full post »
Thread 'A bead-mass oscillatory system problem'

Thread 'A bead-mass oscillatory system problem'

I can't figure out how to find the velocity of the particle at 37 degrees. Basically the bead moves with velocity towards right let's call it v1. The particle moves with some velocity v2. In frame of the bead, the particle is performing circular motion. So v of particle wrt bead would be perpendicular to the string. But how would I find the velocity of particle in ground frame? I tried using vectors to figure it out and the angle is coming out to be extremely long. One equation is by work...
View full post »

Similar threads

Calculate Net Electric Field at Point P | Two Charges 42cm Apart
Replies
4
Views
2K
Calculate Electric Potential from Non-uniform Linear Charge
Replies
20
Views
6K
When is an Electric Field eqn set as - or + ?
Replies
3
Views
2K
Electron moving between 2 point charges
Replies
8
Views
1K
Electric field and potential of 2 point charges
Replies
2
Views
3K
Electric Potential of a Point Charge close to R=0
Replies
6
Views
3K
Having trouble finding the potential between two positive point charges.
Replies
3
Views
2K
Electric Potential due to two charges
Replies
7
Views
5K
I Physics domain analysis of Voltage drop in series resistor
Replies
7
Views
2K
Force on a Point Charge in an Electric Field
Replies
9
Views
3K

Hot Threads

Recent Insights

Back
Top