Sub-units micro-farad and pico-farad

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Doubling the potential difference across a capacitor increases the energy stored, but the relationship is quadratic due to the formula U=(1/2)CV^2. When the voltage (V) is doubled, the energy (U) stored actually increases by a factor of four, not two. The discussion clarifies the distinction between capacitance units, specifically micro-farad and pico-farad, as sub-units of the farad. The key takeaway is understanding how changes in voltage affect energy storage in capacitors. This highlights the importance of correctly applying the energy formula in capacitor-related calculations.
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1. Homework Statement [/b]
If the p.d across a capacitor is doubled, by what factor does the ehnergy stored change?

Define the farad, the unit of capacitance. Explain the commonly used sub-units micro-farad and pico-farad.
 
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What have you done so far? Show your work. What equation might be useful for question #1?
 
V = Q/C ? i don't really undersatnd the question
 
natural said:
V = Q/C ? i don't really undersatnd the question

That's not an equation for energy. You want U=(1/2)CV^2 where U is the stored energy, C is the capacitance, and V is the potential difference.

It's asking if the potential difference is doubled, how much does the energy stored in the capacitor change. So using that equation, if you double V, what happens to U?
 
ooh ok U doubles
 
natural said:
ooh ok U doubles

NO, look more closely. It's V squared, right?
 
increase by 4?
 
That's better.
 
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