Capacitance and electric flux Flashcards
know them all
Q: What is capacitance?
A: The ability of a capacitor to store an electric charge when its plates are at different potentials.
Q: What symbol is used to represent capacitance?
A: Capacitance is represented by the symbol C.
Q: What is the unit of capacitance?
A: The unit of capacitance is the Farad (F).
Q: What is the equation for capacitance?
C= Q/V
, where C = capacitance (F), Q = charge (C), V = potential difference (V).
Q: How is charge represented, and what is its unit?
A: Charge is represented by the symbol Q and is measured in Coulombs (C).
Q: What is 1 Coulomb equal to in terms of electrons?
A: 1 Coulomb =
6.25
×
1
0
18
6.25×10
18
electrons.
Q: How can charge be calculated with current and time?
A:
𝑄
=
𝐼
⋅
𝑡
Q=I⋅t, where Q = charge (C), I = current (A), and t = time (s).
Q: What is electric flux density (D)?
A: Electric flux density is the amount of electric flux passing through a defined area perpendicular to the direction of the flux.
Q: What is the formula for electric flux density?
A:
𝐷
=
𝑄
𝐴
D=
A
Q
, where D = electric flux density (C/m²), Q = charge (C), A = area (m²).
What is the permittivity of free space (
𝜀
0
ε
0
)?
A:
𝜀
0
=
8.85
×
1
0
−
12
F/m
ε
0
=8.85×10
−12
F/m, representing the ratio of electric flux density to electric field strength in a vacuum.
Q: What does relative permittivity (
𝜀
𝑟
ε
r
) represent?
A: The ratio of the insulating power of a material compared to a vacuum.
Q: What is the equation for energy stored in a capacitor?
A:
𝑊
=
1/
2
𝐶
𝑉
2
W=
2
1
CV
2
, where W = energy (J), C = capacitance (F), V = voltage (V).
