3.3 CAPACITANCE Flashcards
1
Q
A capacitor is
A
a device which can store.
The ability to store charge is called capacitance.
Capacotor consist of two conducting plates separated by an insulating layer-| |-
Capacitance is C and measured in farads (F)
2
Q
Charge is directly propotional
A
to Vpd
C=Q/V
3
Q
Charging capacitor
A
copybook 15 p
initially, C=0 and I=E/R
when C charged fully, I=0
4
Q
Discharging graphs
A
opposite direction
5
Q
The magnitude of the initial current is the same for both charging and discharging and depends only on the emf, the resistance,..
A
but not on the value of the capacitor
6
Q
rate of change of a Capacitor
A
student’s note 18 page
7
Q
charge Q is
A
directly propotional to the potential difference (graph is straight line)
8
Q
energy capacitor
A
E=1/2QV
E=1/2 CV2
E=1/2 Q/C2
