PHYS 2113 Midterm: PHYS 2113 LSU form t2 s15
Formula Sheet for LSU Physics 2113, Second Exam, Spring ’15
•Constants, definitions:
g= 9.8m
s2REarth = 6.37 ×106mMEarth = 5.98 ×1024 kg
G= 6.67 ×10−11 m3
kg ·s2RM oon = 1.74 ×106m Earth-Sun distance = 1.50×1011 m
MSun = 1.99 ×1030 kg MM oon = 7.36 ×1022 kg Earth-Moon distance = 3.82×108m
ǫo= 8.85 ×10−12 C2
Nm2k=1
4πǫo
= 8.99 ×109Nm2
C2e= 1.60 ×10−19 C
c= 3.00 ×108m/s mp= 1.67 ×10−27 kg 1 eV = e(1V) = 1.60×10−19 J
dipole moment: ~p =q~
d me= 9.11 ×10−31 kg charge densities: λ=Q
L, σ =Q
A, ρ =Q
V
Area of a circle: A=πr2Area of a sphere: A= 4πr2Volume of a sphere: V=4
3πr3
Area of a cylinder: A= 2πrℓ Volume of a cylinder: V=πr2ℓ
•Units:
Joule = J = N·m
•Kinematics (constant acceleration):
v=vo+at x −xo=1
2(vo+v)t x −xo=vot+1
2at2v2=v2
o+ 2a(x−xo)
•Circular motion:
Fc=mac=mv2
r,T=2πr
v,v=ωr
•General (work, def. of potential energy, kinetic energy):
K=1
2mv2~
Fnet =m~a Emech =K+U
W=−∆U(by field) Wext = ∆U(if objects are initially and finally at rest)
•Gravity:
Newton’s law: |~
F|=Gm1m2
r2Gravitational acceleration (planet of mass M): ag=GM
r2
Gravitational Field: ~g =−GM
r2ˆr=−dVg
dr Gravitational potential: Vg=−GM
r
Law of periods: T2= 4π2
GM !r3Potential Energy: U=−Gm1m2
r12
Potential Energy of a System (more than 2 masses): U=−Gm1m2
r12
+Gm1m3
r13
+Gm2m3
r23
+...
Gauss’ law for gravity: IS
~g ·d~
S=−4πGMins
•Electrostatics:
Coulomb’s law: |~
F|=k|q1|| q2|
r2Force on a charge in an electric field: ~
F=q~
E
Electric field of a point charge: |~
E|=k|q|
r2
Electric field of a dipole on axis, far away from dipole: ~
E=2k~p
z3
Electric field of an infinite line charge: |~
E|=2kλ
r
Electric field at the center of uniformly charged arc of angle φ:|~
E|=λsin(φ/2)
2πǫ0R
Torque on a dipole in an ~
Efield: ~τ =~p ×~
E, Potential energy of a dipole in ~
Efield: U=−~p ·~
E
Document Summary
Formula sheet for lsu physics 2113, second exam, spring "15: constants, de nitions: m s2. Mm oon = 7. 36 1022 kg g = 9. 8. G = 6. 67 10 11 m3 kg s2. Nm2 c = 3. 00 108 m/s dipole moment: ~p = q ~d. Area of a cylinder: a = 2 r volume of a cylinder: v = r2 me = 9. 11 10 31 kg. Earth-moon distance = 3. 82 108 m e = 1. 60 10 19 c. Joule = j = n m: kinematics (constant acceleration): v = vo + at x xo = 1. 2 at2 v2 = v2: + 2a(x xo, circular motion: , v = r: general (work, def. of potential energy, kinetic energy): W = u (by eld) wext = u (if objects are initially and nally at rest) Newton"s law: | ~f | = g r2. Potential energy of a system (more than 2 masses): u = (cid:18)g.
