{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

# lecture16 - RC Circuits RC Discharging a Capacitor...

This preview shows pages 1–5. Sign up to view the full content.

RC Circuits RC Circuits -  circuits in which the currents vary in time -  rate of charging a cap depends on C and R of circuit -  differential equations

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Discharging a Capacitor Discharging a Capacitor ( -  sign because q  decreases for I > 0   That is, current in circuit equals the      decrease of charge on the capacitor) C R q -q I Given:   R, C, q o (initial charge) Find:   q(t)   and   I(t) when switch is closed dt dq I - = 2) 1)    0 = - IR C q (Kirchhoff’s Loop Rule)
C R q -q I RC q dt dq - = where:  q = q(t)         q(0) = q o This is a  differential equation  for the  function  q(t), subject  to the  initial condition  q(0) = q We are looking for a function which is proportional to its own first  derivative (since dq/dt ~ -q).  Combine 1) and 2) to get:

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
RC  is called the “time constant ” or “characteristic time” of the circuit.
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 14

lecture16 - RC Circuits RC Discharging a Capacitor...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online