- #1

Guillem_dlc

- 184

- 15

- Homework Statement
- If an infinite straight wire loaded with a linear density [itex]\lambda =10^{-8}\, \textrm{C/m}[/itex] creates a potential of [itex]239\, \textrm{V}[/itex] at a distance of [itex]8\, \textrm{m}[/itex] from the wire, calculate at what distance [itex]r_0[/itex] from the wire is the origin of potentials [itex] V(r=r_0)=0[/itex]. Express the result in [itex]\textrm{m}[/itex].

a) [itex]114[/itex]

b) [itex]10.6[/itex]

c) [itex]+\infty[/itex]

d) [itex]30.2[/itex]

- Relevant Equations
- [tex]V(r)=\dfrac{kq}{r}[/tex]

I think the right choice is c. I'll pass on my reasoning to you:

We can think that if the formula of the potential is

[tex] V(r)=\dfrac{kq}{r} [/tex]

If [itex]r[/itex] tends to infinity, then [itex]V(r)=0[/itex].

But the correct answer is d).

We can think that if the formula of the potential is

[tex] V(r)=\dfrac{kq}{r} [/tex]

If [itex]r[/itex] tends to infinity, then [itex]V(r)=0[/itex].

But the correct answer is d).