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GRE Physics

Instructions:

Answer 50 questions in 15 minutes.
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Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. Energy in terms of partition function
U = t^2 d/dt (logZ)
B = µ0 I n
Sin(?) = ?/d
F = µ0 q v I / 2pr

2. Relativistic Energy
?mc²
4H + 2e- ? He +2? + 6?
X_L = X_C or X_total = 0
v(mean)

3. td(entropy) =
1/f = (n-1)(1/R1 - 1/R2) if both positive - they are convex - concave
W' = (w-v)/(1-w v/c^2) ; observer in S sees an object moving at velocity w; another frame S' moves at v wrt S.
PdV +dU
?~T

4. Thermo: Partition Function
Z = ?g_i*exp(-E/kT)
North to south; Earth has S magnetic pole at the N geographic pole and vice versa.
P(s) = (1/Z) Exp[-E(s)/(k T)] Z = S_s(Exp[-E(s)/(k T)])
W' = (w-v)/(1-w v/c^2) ; observer in S sees an object moving at velocity w; another frame S' moves at v wrt S.

5. Single Slit Diffraction Intensity
I = Im (sinc²(a)) ; a = pai sin(?) / ?
1/ne - where n is charge carrier density
Q = CVexp(-t/RC)
North to south; Earth has S magnetic pole at the N geographic pole and vice versa.

6. A reversible process stays..
Infinitely close to equilibrium at all times
? = ?0 root((1-v/c)/(1+v/c))
ds² = (c*dt)² - ?(x_i)²
North to south; Earth has S magnetic pole at the N geographic pole and vice versa.

7. Adiabatic means
Exponential - E = -ma²/2hbar² - a is strength of delta wellt
Isentropic
Opposing charge induced upon conductor
?s = 0 - ?l = ±1

8. Perpendicular axis theorem
In Zeeman effect - the contribution of electron spin to total angular momentum means that it isn'T always three lines and they are not always equally spaced.
I_z = I_x + I_y (think hoop symmetry)
P +1/2 ? v² + ?gh = Constant
E_n = -µ c^2 Z a^2 / (2n^2) - with µ = m_1 m_2 / (m_1 + m_2)

9. Magnetic Field For Current in Long Wire
Isentropic
E = s/e_0
µ0 I / 2pR
X_L = i?L

10. Thermo: 1st Law
I = I_cm + (1/2)m d^2
0
dQ = dW +dU
P(s) = (1/Z) Exp[-E(s)/(k T)] Z = S_s(Exp[-E(s)/(k T)])

11. Polarizers - intensity when crossed at ?
Z_C + Z_L = 0. Occurs when ?=1/Sqrt[L C]
I = I_0 Cos[?]^2
? (t-vx/c²)
µ = Current * Area T = µ x B

12. Mech: Centripetal Force
F = s * T4
E_n = -µ c^2 Z a^2 / (2n^2) - with µ = m_1 m_2 / (m_1 + m_2)
F = mv²/r
Const: 2t = (n +.5)? Destructive 2t = n?

13. Helmholtz Free Energy
µ0 I / 2R
V = -L di/dt
DW/dq
U - ts = -tlog(Z)

14. Wein'S displacement law for blackbodies (? and T)
?_max = b/T
L^2 |E - scl - m> = hbar^2 scl(scl+1) |E -scl -m> L_z |E - scl - m> = hbar m |E - scl - m>
? = ?_0 Sqrt[(1+v/c)/(1-v/c)]
Exponentially decreasing radial function

15. Mean electron drift speed
J/(ne) n: atom density
V = V0 + V0 a ?T
Dp/dt = L / (t ?V)
W_A < W_I

16. Energy levels from the Coulomb potential
E_n = -µ c^2 Z a^2 / (2n^2) - with µ = m_1 m_2 / (m_1 + m_2)
? = 5/3
Exponential - E = -ma²/2hbar² - a is strength of delta wellt
Sin(?) = ?/d

17. Kepler'S Three Laws
Exp(N(µ-e)/t)
D/dt (.5*r^2 d?/dt) = 0 - r(?) = a(1-e²)/(1+ecos(?)) - T²aA³
<T> = -<V>/2
Opposing charge induced upon conductor

18. Kepler'S third law (T and R)
?~T
T^2 = k R^3 - k=constant
µ=s^2
0

19. Mech: Impulse
J = ? Fdt
Interference: (m+.5)? = d sin(?) Diffraction: m? = w sin(?)
P1V1 - P2V2 / (? - 1)
? = 5/3

20. Lab: Precision of Measurements
H = T + V;qdot_i = dH/dp_i - pdot_i = dH/dq_i
Measurements close to mean
L = L_0 Sqrt[1-v^2/c^2]
?? = h/mc * (1-cos(?))

21. Rotation matrix (2x2)
?s = 0 - ?l = ±1
.5 LI²
Cos[?] Sin[?] -Sin[?] Cos[?]
C_eq = (? 1/C_i)^-1

22. E field of a capacitor (d->0)
E = Z²*E1
Const: 2t = (n +.5)? Destructive 2t = n?
V = V0 + V0 a ?T
E = s/e_0

23. Quant: Expectation Value
DS = 0 - dQ = 0 - P V^? = constant
P² ~ R³
<?|O|?>
Hbar*?³/(p²c³exp(hbar?/t)-1)

24. Center of Mass: Kinetic Energy & Angular Momentum
Q = CVexp(-t/RC)
U = t^2 d/dt (logZ)
KE = 1/2 * µ (dr/dt)² L = µ r x v
I_z = I_x + I_y (think hoop symmetry)

25. Energy for orbits: Hyperbole - Ellipse - Parabola - Circle
B = µ0 I n
ma + kx = 0
1/vLC
E = Vmin : circle - E = 0 : parabola - E<0 : el - E>0 : h

26. EM: Reactance of Inductor
I = I_cm + md²
T^2 = k R^3 - k=constant
?? = h/mc * (1-cos(?))
X_L = i?L

27. Thin Film Theory: Constructive / Destructive Interference
Const: 2t = (n +.5)? Destructive 2t = n?
W' = (w-v)/(1-w v/c^2) ; observer in S sees an object moving at velocity w; another frame S' moves at v wrt S.
?? = h/mc * (1-cos(?))
?scl = +/-1;?m = 0 - +/-1;?S_tot = 0;(?j = ?scl + ?S_tot)

28. Adiabatic processes (dS - dQ - P and V)
<T> = -<V>/2
C_eq = ?C_i
P/A = s T^4
DS = 0 - dQ = 0 - P V^? = constant

29. Atom: Hydrogen Wave Function Type
Let w_i = 1/s_i^2;x_wav = S(w_i x_i) / Sw_i - s_xwav = 1/Sw_i
Exponentially decreasing radial function
U = t^2 d/dt (logZ)
I ' = I cos²(?)

30. Quant: Eigenvalue of Hermitian Operator
Always Real
V = V0 + V0 a ?T
?L/A - L = length - A = cross sectional area - rho is electrical resistivity
v(mean)

31. EM: Lorentz Force
F = I L X B
E²-p²c²
<T> = 1/2 * <dV/dx>
F = qv×B

32. EM: Bremsstrahlung (translation)
Product ( nj ^ vj ) = Product(nqj ^ vj exp (-vj F(int)/Tau))
Braking Radiation
F = s * T4
E ~ (1/(n_f)² - 1/(n_i)²) ~ 1/?

33. Planck Radiation Law
Hbar*?³/(p²c³exp(hbar?/t)-1)
Cv = dE/dT = 3R
? = 1.22? / d
N d flux / dt

34. Mech: Force of Friction
N d flux / dt
F_f = µ*F_N
P² ~ R³
Let w_i = 1/s_i^2;x_wav = S(w_i x_i) / Sw_i - s_xwav = 1/Sw_i

35. Mech: Rotational Energy
Sin(?) = ?/d
T = I?²/2
Ct²-x²-y²-z²
Dv = -udm/m - v = v0 + u ln(m0/m)

36. Current in resistor in RC circuit
?_max = b/T
When you apply a uniform electric field - it induces a dipole moment and interacts with it - and that effect depends on |mj |. So if j is an integer - splits (asymmetrically) into j+1 levels - and if j is a half integer - splits (asymmetrically) into
I = V/R exp(-t/RC)
?~T

37. Wein'S Displacement Law
?max = 2.898 x 10 -³ / T
?scl = +/-1;?m = 0 - +/-1;?S_tot = 0;(?j = ?scl + ?S_tot)
B = µ0 I n
?L/A - L = length - A = cross sectional area - rho is electrical resistivity

38. Atom: Bohr Formula
E ~ (1/(n_f)² - 1/(n_i)²) ~ 1/?
1/2 CV²
? = ?_0 Sqrt[(1+v/c)/(1-v/c)]
Measurements close to true value

39. Selection Rules
?s = 0 - ?l = ±1
U - ts = -tlog(Z)
µ = m_e/2
?mv

40. Doppler shift for light
Exponential - E = -ma²/2hbar² - a is strength of delta wellt
?= h/v(2mE)
I = I_cm + (1/2)m d^2
? = ?_0 Sqrt[(1+v/c)/(1-v/c)]

41. 3 Laws of Thermo
qvb = mv²/R
1. Heat is energy 2. Entropy never decreases 3. Entropy approaches a constant value as t -> 0...
Measurements close to mean
N d flux / dt

42. Stoke'S Theorem
(3/2) n R ?t
Opposing charge induced upon conductor
V = V0 + V0 a ?T
Int ( A . dr) = Int ( del x A) dSurface

43. Charge in Capacitor
L = µ N² A / l : N = number of turns - A = cross sectional area -l = length
Q = CVexp(-t/RC)
DW/dq
B = µ0 I (sin(?1)-sin(?2))/(4pr) r = distance from point

44. Rocket Thrust
I = Im (sinc²(a)) ; a = pai sin(?) / ?
qvb = mv²/R
X_L = i?L
u dm/dt

45. Work in a capacitor
B = µ0 I n
1/2 CV²
N²/Z (m_elec/m_red)
B = µ0 I (sin(?1)-sin(?2))/(4pr) r = distance from point

46. Gibbs Factor
X_L = X_C or X_total = 0
U = t^2 d/dt (logZ)
Exp(N(µ-e)/t)
Hbar*?³/(p²c³exp(hbar?/t)-1)

47. Self Inductance
V = -L di/dt
C_eq = ?C_i
M? = 2dsin(?)
KE = 1/2 * µ (dr/dt)² L = µ r x v

48. Poisson distribution (µ and s)
u dm/dt
V = -L di/dt
?max = 2.898 x 10 -³ / T
µ=s^2

49. Thermo: Blackbody Radiation
F = s * T4
S_mean = s/Sqrt[N]
? = ?_0 Sqrt[(1+v/c)/(1-v/c)]
I = I_cm + md²

50. Weighted average (mean and unc. of mean)
Isentropic
Let w_i = 1/s_i^2;x_wav = S(w_i x_i) / Sw_i - s_xwav = 1/Sw_i
Faraday/Lenz: current inducted opposes the changing field
Exponentially decreasing radial function