Electrostatic potential and capacitance

AI Thread Summary
The discussion revolves around calculating the maximum potential difference across a series of capacitors with given capacitances (120 µF, 40 µF, and 50 µF) and a voltage limit of 50V for each capacitor. The approach involves finding the equivalent capacitance and using the formula Q=CV to determine charge and voltage across each capacitor. The net charge from the battery is equal to the charge on each capacitor due to their series connection. The maximum voltage across any capacitor cannot exceed 50V, leading to an equation to solve for the battery's emf (V). Ultimately, the solution aims to equate the maximum voltage across the capacitors to the given limit to find the required value of V.
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Homework Statement


C120 uF C2=40uF C3= 50uF if no capacitor has the capacity to bear more than 50V then maximum potential difference between the two ends is


Homework Equations



Q=CV


The Attempt at a Solution


i tried by calculating the Ceq then putting it in the equation finding out q i know it doesn't make sense...

Just help me..
 
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let emf of battery is V

Find net q through battery

then find q on each capacitor and thus calculate voltage of each

Now maximum voltage you find cannot exceed

then calculate V
 
cupid.callin said:
let emf of battery is V

Find net q through battery

then find q on each capacitor and thus calculate voltage of each

Now maximum voltage you find cannot exceed

then calculate V

q(battery) = q on each capacitor as the conection is made in series (sorry forgot to mention that
)
 
nyways answer will not come by this method it will result into the given variable

let V be the emf of battery
then q= C (eq) V
q= 200/19 V

now you suggest to find V' thre are two variables above so can't find that either
 
q = 200/19 V

so potential on each capacitor is : (200V/19)/20 , (200V/19)/40 , (200V/19)/50

now the maximum of these is equal to 50 (given)

so equate and find V

answer:
V = 95
 
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