Friday

August 22, 2014

August 22, 2014

Posted by **Mary** on Thursday, January 26, 2012 at 10:45pm.

- Physics!! Help!!!!! -
**Damon**, Thursday, January 26, 2012 at 11:03pmC = q/V

q = C V

i = -dq/dt = -C dV/dt

but V = i r

so

i = -C r di/dt

i + C r di/dt = 0

V/r + C r (1/r) dV/dt) = 0

V + r C dV/dt = 0

dV/dt = -1/rC V

dV/V = -1/rC dt

ln V = - (1/rC) t

V = Vi e^-(1/RC)t

- Physics!! Help!!!!! -
**Damon**, Thursday, January 26, 2012 at 11:12pmlet T = RC

then

V = Vi e^-t/T

if RC = 10^6 * 220*10^-6 = 220 = T

Vi = 24

V = 24 e^-t/220

if t = 100

V = 24 e^-(100/220) = 24 e^-.454

= 24*.635 = 15.2

You can do the change for new C and R and get error in V

**Related Questions**

physics - What is the voltage across a capacitor after a time of two constants ...

Physics Help! - A 220 uF capacitor with a 10% tolerance rating is charged. The ...

physics - In the circuit below, at time t = 0, the switch is closed, causing the...

Physics- Repost (Answer did not make sense) - In the circuit below, at time t...

Physics - The circuit below consists of three identical resistors each with ...

Physics - Two identical capacitors store different amounts of energy: capacitor ...

Physics - Two identical capacitors store different amounts of energy: capacitor ...

Calculus - A 15.2-F capacitor has an initial voltage of 2.00 V. It is charged ...

physics - please help:- Two capactiors of 14microfarror and 6 microfarror are ...

Physics -conceptual - A 1 mF, a 2 mF, and a 3 mF capacitor are connected in ...