Time needed to reduce charge of a capacitor

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SUMMARY

The discussion centers on calculating the time required to discharge a 20 µF capacitor from an initial charge of 20 µC to a final charge of 8 µC through a 1.0 kΩ resistor. The relevant equation for this problem is I = dQ/dt, where dQ is the change in charge. Participants emphasize the need to determine the initial voltage across the capacitor to effectively apply the discharge equations and calculate the time constant for the RC circuit.

PREREQUISITES
  • Understanding of capacitor discharge equations
  • Familiarity with Ohm's Law
  • Knowledge of time constant in RC circuits
  • Basic concepts of electric charge and capacitance
NEXT STEPS
  • Learn how to calculate the time constant (τ) for an RC circuit
  • Study the relationship between charge, voltage, and capacitance in capacitors
  • Explore the exponential decay of charge in capacitors
  • Investigate practical applications of capacitors in electronic circuits
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Students studying electrical engineering, physics enthusiasts, and anyone looking to understand capacitor discharge behavior in RC circuits.

catan
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Homework Statement


A 20 uF capacitor initially charged to 20 uC is discharged through a 1.0 kOlhms resistor. How long does it take to reduce the capacitor's charge to 8.0 uC?




Homework Equations



I=dQ/dt



The Attempt at a Solution



I know that dQ = 12 uC. What I can't figure out is how to get I from the given data. I'm assuming I need to use the 20 uF along with the resistance to find the I but I don't know how that can be done. I appreciate any help, thanks!
 
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catan said:

Homework Statement


A 20 uF capacitor initially charged to 20 uC is discharged through a 1.0 kOlhms resistor. How long does it take to reduce the capacitor's charge to 8.0 uC?




Homework Equations



I=dQ/dt



The Attempt at a Solution



I know that dQ = 12 uC. What I can't figure out is how to get I from the given data. I'm assuming I need to use the 20 uF along with the resistance to find the I but I don't know how that can be done. I appreciate any help, thanks!

I think you need more relevant equations. Do you know what the initial voltage is across the capacitor?
 
I figured it out
 

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