Physics Sheet

Some Helpful Equations

E = F/qo FCoulomb = k |q1q2|/r2 k = (1/4) = 9 x 109 N-m2/C2 = 8.854 x 10-12 C2/N-m2

E = E * dA (over closed surface) = (qenc/)
e = 1.6 x 10-19 C me = 9.1 x 10-31kg

E = dE = [k dq/r2] (r/r) dq = dl = dA = dV
Asphere = 4r2 Acyl (lateral) = 2rL

Volumesphere = (4/3)r3 E = /o U = qoV U = - F * dl
Fx = - U/x U = kq0qi/ri


V = kqi/ri V = U/qo
Va- Vb = Vab = E* dl
Ex = - dV/dx - Wfield = U = Wext

= (1/2)E2
= Ko
C = KCo
E = Eo/K
V = Vo/K


1/Cser = 1/C1+ 1/C2+1/C3 +....
Cpar. = C1 + C2 + C3 +....
C = Q/Vab
U = QV/2

U = (1/2) CV2 = Q2/(2C) I = dQ/dt J = I/A = nqvd R
=
L/A
Rser = R1 + R2 + R3+ ...

1/Rpar = 1/R1 + 1/R2 +1/ R3+ ...
V = IR
P = IV = I2R = V2/R P =F * v Vi = 0

I = 0
q(t) = C(1 - e-t/(RC)) i(t) = Ioe-t/(RC) Io = /R

F = qv x B
F = qvBsin dF = Idl x B
= B * dA ac = v2/R

= RC
= NIA
= x B
qvB = mv2/R
= v/R
f = /(2)

v = E/B
B = [o/(4)]qv x r/r3
c2 = (oo)-1 dB = [o/(4)]Idl x r/r3
B = oI/(2r)

F/L = oII'/((2r)
B * dl = oIenclosed (over closed loop)
= - d/dt
= - Blv

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