2.1 CAPACITANCE & CAPACITORS IN SERIES AND PARALLEL capacitor and dielectric capacitor and dielectric Define and use capacitance capacitor ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ' ! ! ! ! ! ! ! ! ! ! ! :
capacitance capacitance 1 farad magnitude of charge on either plate potential difference between two plates ,C
Example 1 Example 1 Example 1 Example 1 What voltage required to stored 9.6×10-4 of charge on the plates of a 6.0mF capacitor ? C = Q T V = Qc = 9.6×10-6 6. 0×10-6 = 1.6 V T "
Derive the effective capacitance of capacitor in series and parallel , JOU V1 f-V2 3¥ 300 30 ( = § 4=4-1 V2 1=1%+1.5'
Example 2 Example 2 Calculate equivalent capacitance and total charge of the circuit equivalent capacitance total charge 6mF 3µF 4mF 1.33nF C, Cz C} CT I 1- 30 V 30 V C, , Cz and Cz ( s) Q:-(TV 1- = = (1.33×10-9/30) E. + CT ¥+1T, = 3.99×10-5 C " E. =Éu+÷u+Eu 4=4-1%+4 " CT = I -33mF "
Example 3 Example 3 Calculate equivalent capacitance and total charge of the circuit equivalent capacitance total charge 3µF C , 13nF | 4m6µF ( I 3 30V 30V C , ,Cz8C3 (p ) CT __ C , + Cztcz QT = CTV = 13×10-6130) = 3m -14m -16m = 3.9×10-4C =/ 3uc - " - "
Calculate equivalent capacitance and total charge of the circuit Example 4 equivalent capacitance total charge 3mF 4mF I -71mF → I CI 6µF (2 @I 6µF ( @@ 3 ( 3 @ 30V 30V C, and Cz ( s) 7.71mF E. =É+É a 42=(4-+15)" 30V a- =/ In -1%1" = 1.71mF QT=CtV Chand (3 7 = 7.71×10-6130) ¥? " ( 1- = (iz -1 ( 3 = 1.71M -16M ( 1- = 7.71mF
Calculate equivalent capacitance of the circuit Example 5 Example 5 equivalent capacitance 3nF 1.2mF • C , ° ( 12 | G- 4µF G- 4nF 1nF 2µF 1mF ( 4 Cz ( 4 ( 3 ( 3 / • • 6nF 6nF Cizandcycp) 6124 = 421-64 C , and Cz (s ) = 1.2Mt 4M I =L, -1L, = 5.2mF ( 12 - I g - Ciz = {, + {z G- 5.2mF 1µF (12 = ( 124 3M 2M ( 3 1. 2mF • 6µF ( 124 and C} ( s) I = ( 1243 ( 124 + (3 ( 1243 = + ( C} 124 ( 1243 = + 5.2M 6M = 2.79mF
• - Cizyz and C5Cp) G- 2.79mF 1µF ( 1- = C1243 + ( 5 ( 1243 = 2.79M 1- IM • - - = 3.79mF 1 " 8 G- 3.79nF •
Derive energy stored in a capacitor energy stored in capacitor energy stored in capacitor W =qV - -
2.2 CHARGING AND DISCHARGING CAPACITORS capacitor and dielectric capacitor and dielectric ,
e e e ¥ ¥ ee e e ←vc→ e = e Vo E e e e ee ee e e e e -1+1 +* +* ' n e e ←vc→ e = OV e e e e e e e e
charging discharging
Time constant Time constant I
2.3 CAPACITOR WITH DIELECTRIC capacitor and dielectric capacitor and dielectric Dielectric Dielectric C=Eo÷rA C = Ega ¥ 9C = EFI 㱺
Define dielectric constant Dielectric constant Dielectric constant the dielectric meterial contains polar molecules and are random orientation ( unpolarized)
Describe the effect of dielectric on a parallel plate capacitor E!ect of dielectric on para ect of dielectric on paralel plate capacitor el plate capacitor ✓= Ed c-- EID