What is the new separation between the charges?

AI Thread Summary
The discussion focuses on calculating the new separation distance between two positive point charges after their electric potential energy doubles. The initial separation is 0.86 m, and the potential energy formula used is PE = kQ_aQ_b/d. By simplifying the equation and canceling common terms, the new distance is derived as d = 0.43 m. The calculation confirms that the new separation is correct. The solution demonstrates the application of electric potential energy principles in determining charge separation.
kdrobey
Messages
27
Reaction score
0

Homework Statement




Two positive point charges are held in place, 0.86 m apart. They are then moved so that their electric potential energy doubles. What is the new separation between the charges?

Homework Equations



kq/r

The Attempt at a Solution


had PEb=KQaQb/d=2EPEa, then did KQaQb/d=2(KQaQb/.86. but cannot figure out how to solve it further
 
Physics news on Phys.org
kdrobey said:
... then did KQaQb/d=2(KQaQb/.86.
This is good. Simply and solve for d. Start by canceling everything that can be canceled from both sides of the equation.
 
both sides of the equation had KQaQb, i canceled the part out on both sides, leaving, 1/d=2(1/.86). then 1=2.32d. d=.43?
 
Looks good to me.
 
awesome, thanks
 

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 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
View full post »

Similar threads

Charge separation of O-H bond in water molecule?
Replies
12
Views
905
Electric Potential Energy of Point Charge Systems
Replies
2
Views
941
What is the magnitude of the field at point R?
Replies
5
Views
2K
Charge on a grounded conducting sphere in a uniform electric field, after ungrounding and movement
Replies
1
Views
1K
Is it possible for opposite charges to repel each other?
Replies
7
Views
2K
Van der Graaf Generator: Charge, Potential and Redesign Questions
Replies
8
Views
2K
How Do You Calculate the Initial Separation Between Two Charged Particles?
Replies
20
Views
4K
Minimum force to separate two oppositely-charged ions
Replies
8
Views
3K
MIT OCW, 8.02 Electromagnetism: Potential for an Electric Dipole
Replies
1
Views
2K
Electric force calculate the separation
Replies
3
Views
1K

Hot Threads

Recent Insights

Back
Top