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Potential due to point charge

  • Thread starter stylez03
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  • #1
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Homework Statement


The electric potential at a distance of 20.5 cm from a very small charged sphere is 33.0 V, with the potential taken to be zero at an infinite distance from the sphere.

If the sphere is treated as a point charge, what is its charge?

Homework Equations



[tex] V = \frac {U} {q_{0}} == \frac {1} {4*pi*(8.85*10^{-12})}*\frac {q} {r} [/tex]

The Attempt at a Solution



How do you convert 33.0V to the correct units of Q or is it equliv?

[tex] \frac {1} {4*pi*(8.85*10^{-12})}*\frac {33.0} {0.255} [/tex] ??
 

Answers and Replies

  • #2
Hootenanny
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You don't need to convert your potential into anything, you already have an expression for V, so use it;

[tex]V = k\cdot\frac{q}{r} \Leftrightarrow q = \frac{V\cdot r}{k}[/tex]

Also note that [itex]20.5 cm \neq 0.255 m[/itex], its probably just a typo.
 
  • #3
139
0
You don't need to convert your potential into anything, you already have an expression for V, so use it;

[tex]V = k\cdot\frac{q}{r} \Leftrightarrow q = \frac{V\cdot r}{k}[/tex]

Also note that [itex]20.5 cm \neq 0.255 m[/itex], its probably just a typo.
Thank you, yes that was a typo.
 

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