Electrical Potential at point Y between 2 point charges

AI Thread Summary
The discussion centers on calculating the electric potential at point Y between two charges, +1.5 x 10^-2 C and -2.7 x 10^-5 C, which are 20 cm apart. The electric field at point Y is determined to be 5.4 x 10^10 N/C. The user successfully calculated the individual potentials from each charge but is unsure about the formula for total potential. The calculations for the potentials yielded v1 = 2.7 x 10^9 V and v2 = -1.62 x 10^6 V, leading to a total potential of 2.7 x 10^9 V. Overall, the user's approach appears correct, but clarification on the formula for total potential is needed.
BN Joe
Messages
1
Reaction score
0

Homework Statement



Two charges, one of charge +1.5 x 10^–2 C and the other of charge –2.7 x 10^5 C, are 20.0 cm apart. The positive charge is to the left of the negative charge.
(a)Draw a diagram showing the point charges and label a point Y that is 5.0 cm away from the positive charge, on the line connecting the charge and between the two charges. (Field lines need not be drawn.)
(b)Calculate the electric field at point Y.
(c)Calculate the electric potential at point Y

q1 = 1.5 x 10^-2 C
q2 = -2.7 x 10^-5 C
d = 0.2m
k = 9 x 10^9

Homework Equations



Not sure... possibly
v = kq1 / d

The Attempt at a Solution



I had no issues with parts a and b, but I am not sure of the correct formula to solve part c and the answer I got doesn't seem to make sense.
If it helps the electric field at point y is 5.4 x 10^10 N/C

V = kq1 / d
v1 = (9 x 10^9)(1.5 x 10^-2C) / 0.05m
= 2.7 x 10^9
v2 = (9 x 10^9)(-2.7 x 10^-5C) / 0.15m
= -1.62 x 10^6
Vtotal = v1 + v2
= 2.7 x 10^9 V
 
Physics news on Phys.org
BN Joe said:

Homework Statement



Two charges, one of charge +1.5 x 10^–2 C and the other of charge –2.7 x 10^5 C, are 20.0 cm apart. The positive charge is to the left of the negative charge.
(a)Draw a diagram showing the point charges and label a point Y that is 5.0 cm away from the positive charge, on the line connecting the charge and between the two charges. (Field lines need not be drawn.)
(b)Calculate the electric field at point Y.
(c)Calculate the electric potential at point Y

q1 = 1.5 x 10^-2 C
q2 = -2.7 x 10^-5 C
d = 0.2m
k = 9 x 10^9

Homework Equations



Not sure... possibly
v = kq1 / d

The Attempt at a Solution



I had no issues with parts a and b, but I am not sure of the correct formula to solve part c and the answer I got doesn't seem to make sense.
If it helps the electric field at point y is 5.4 x 10^10 N/C

V = kq1 / d
v1 = (9 x 10^9)(1.5 x 10^-2C) / 0.05m
= 2.7 x 10^9
v2 = (9 x 10^9)(-2.7 x 10^-5C) / 0.15m
= -1.62 x 10^6
Vtotal = v1 + v2
= 2.7 x 10^9 V

Your calculations look fine.
 

Thread 'Errors and significant figures'

I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
View full post »
Thread 'Collision of a bullet on a rod-string system: query'

Thread 'Collision of a bullet on a rod-string system: query'

In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
View full post »
Thread 'A cylinder connected to a hanging mass'

Thread 'A cylinder connected to a hanging mass'

Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
View full post »

Similar threads

Find the magnitude of the electric field at point P
Replies
5
Views
2K
Calculate Net Electric Field at Point P | Two Charges 42cm Apart
Replies
4
Views
2K
Electric Potential Energy of Point Charge Systems
Replies
2
Views
878
Electric field created by point charges
Replies
6
Views
755
Potential difference between two points in an electric field
Replies
1
Views
2K
Van der Graaf Generator: Charge, Potential and Redesign Questions
Replies
8
Views
2K
Uniform charge density and electric potential
Replies
4
Views
3K
Electric field due to three point charges
Replies
4
Views
2K
Kinetic and potential energy of a particle attracted by charged sphere
Replies
6
Views
1K
Electric field at the center of the equilateral triangle
Replies
10
Views
3K

Hot Threads

Recent Insights

Back
Top