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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. EM: Series Capacitance
T = I?²/2
C_eq = (? 1/C_i)^-1
DB = ( µ_0 I/(4Pi) ) dl(cross)rhat/r^2
F = s * T4

2. Induced EMF of solenoid
? = ?0 root((1-v/c)/(1+v/c))
ds² = (c*dt)² - ?(x_i)²
N d flux / dt
? (t-vx/c²)

3. Compton Scattering
E = Z²*E1
?? = h/mc * (1-cos(?))
CdV/dt + V/R = 0 V(t) = V0 exp(-t/RC) I(t) = I(0) exp(-t/RC)
I = -(c ?t)^2 + d^2

4. Virial Theorem
<T> = 1/2 * <dV/dx>
Interference: (m+.5)? = d sin(?) Diffraction: m? = w sin(?)
dU = 0 ? dS = ?dW/T
F_f = µ*F_N

5. Hall Coefficient
Sin(?) = ?/d
N²/Z (m_elec/m_red)
C_eq = (? 1/C_i)^-1
1/ne - where n is charge carrier density

6. Invariant Energy Quantity
E²-p²c²
X_L = i?L
Const: 2t = (n +.5)? Destructive 2t = n?
1/f = (n-1)(1/R1 - 1/R2) if both positive - they are convex - concave

7. Doppler Shift in Frequency
Interference: (m+.5)? = d sin(?) Diffraction: m? = w sin(?)
F = f* (c+v_r)/(c+v_s)
div(E) = ?/e_0 - curl(E) = der(B)/der(t) - div(B) = 0 - curl(B) = µ_0J + µ_0e_0*der(E)/der(t)
Infinitely close to equilibrium at all times

8. Entropy (# of states - and in terms of other thermo quantities)
I = I_cm + md²
IR + Ldi/dt = 0 - I = I0e(-tL/R) Work = 1/2 L I0^2
P +1/2 ? v² + ?gh = Constant
S = k ln[O] ; dS = dQ/T

9. Thermo: Monatomic gas ?=?
<?|O|?>
? = 5/3
F = -2*m(? x r)
L^2 |E - scl - m> = hbar^2 scl(scl+1) |E -scl -m> L_z |E - scl - m> = hbar m |E - scl - m>

10. Single Slit Diffraction Maximum
Asin(?) = m?
u dm/dt
?_max = b/T
(3/2) n R ?t

11. Mech: Impulse
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.
N²/Z (m_elec/m_red)
E = <?| H |?>
J = ? Fdt

12. QM: de Broglie Wavelength
Product ( nj ^ vj ) = Product(nqj ^ vj exp (-vj F(int)/Tau))
?= h/v(2mE)
1/f = (n-1)(1/R1 - 1/R2) if both positive - they are convex - concave
KE = 1/2 * µ (dr/dt)² L = µ r x v

13. A reversible process stays..
Infinitely close to equilibrium at all times
M? = 2dsin(?)
X_L = i?L
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.

14. Error in the mean if each measurement has the same uncertainty s
Q = U + W Q = heat in system - U = total energy in system - W = work done by gas
Measurements close to true value
M? = 2dsin(?)
S_mean = s/Sqrt[N]

15. Energy in terms of partition function
E ~ (1/(n_f)² - 1/(n_i)²) ~ 1/?
U = t^2 d/dt (logZ)
F_f = µ*F_N
I = -(c ?t)^2 + d^2

16. td(entropy) =
PdV +dU
?? = h/mc * (1-cos(?))
T^2 = k R^3 - k=constant
Asin(?) = m?

17. Springs in series/parallel
S_mean = s/Sqrt[N]
E = Vmin : circle - E = 0 : parabola - E<0 : el - E>0 : h
Series: 1/k_eq = 1/k_1 + 1/k_2; Parallel: k_eq = k_1 + k_2
v(mean)

18. Single Slit Diffraction Intensity
Triplet: symmetric - net spin 1 Singlet: antisymmetric - net spin 0
I = Im (sinc²(a)) ; a = pai sin(?) / ?
F_f = µ*F_N
N²/Z (m_elec/m_red)

19. Invariant spatial quantity
Ct²-x²-y²-z²
?? = h/mc * (1-cos(?))
C_eq = ?C_i
North to south; Earth has S magnetic pole at the N geographic pole and vice versa.

20. Astro: Aperture Formula (Rayleigh Criterion)
? = ?_0 Sqrt[(1+v/c)/(1-v/c)]
P1V1 - P2V2 / (? - 1)
L = T - V dL/dq = d/dt dL/dqdot
? = 1.22?/D

21. Stark Effect
L = T - V dL/dq = d/dt dL/dqdot
I ' = I cos²(?)
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
N²/Z (m_elec/m_red)

22. Pauli matrices
F = s * T4
S = (hbar/2) s ;with S = S_x xhat + S_y yhat + S_z zhat -s = s_x xhat + s_y yhat + s_z zhat
E = Z²*E1
.5 CV²

23. Wein'S Displacement Law
P/A = s T^4
?max = 2.898 x 10 -³ / T
I = I_0 Cos[?]^2
.5 CV²

24. Planck Radiation Law
Hbar*?³/(p²c³exp(hbar?/t)-1)
µ=s^2
1. Heat is energy 2. Entropy never decreases 3. Entropy approaches a constant value as t -> 0...
1/2 CV²

25. Radiation (Larmor - and another neat fact)
L = T - V dL/dq = d/dt dL/dqdot
div(E) = ?/e_0 - curl(E) = der(B)/der(t) - div(B) = 0 - curl(B) = µ_0J + µ_0e_0*der(E)/der(t)
?s = 0 - ?l = ±1
P = µ_0 q^2 a^2/(6Pi c); No radiation along the axis of acceleration

26. Work (P - V)
ih_barL_z
P1V1 - P2V2 / (? - 1)
E = <?| H |?>
?L/A - L = length - A = cross sectional area - rho is electrical resistivity

27. EM: Reactance of Capacitor
X_C = 1/(i?C)
1. Heat is energy 2. Entropy never decreases 3. Entropy approaches a constant value as t -> 0...
I = I_0 Cos[?]^2
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

28. Parallel axis theorem
? (t-vx/c²)
S = k ln[O] ; dS = dQ/T
?scl = +/-1;?m = 0 - +/-1;?S_tot = 0;(?j = ?scl + ?S_tot)
I = I_cm + (1/2)m d^2

29. Lab: Accuracy of Measurements
X_L = i?L
Measurements close to true value
F = s * T4
1/f = (n-1)(1/R1 - 1/R2) if both positive - they are convex - concave

30. Stoke'S Theorem
J/(ne) n: atom density
PdV +dU
C_eq = ?C_i
Int ( A . dr) = Int ( del x A) dSurface

31. Energy levels from the Coulomb potential
Let w_i = 1/s_i^2;x_wav = S(w_i x_i) / Sw_i - s_xwav = 1/Sw_i
?_max = b/T
Z²/n² (m_red/m_elec)
E_n = -µ c^2 Z a^2 / (2n^2) - with µ = m_1 m_2 / (m_1 + m_2)

32. Polarizers - intensity when crossed at ?
qvb = mv²/R
Exp(N(µ-e)/t)
I = I_0 Cos[?]^2
dQ = dW +dU

33. Rocket Equation
Dv = -udm/m - v = v0 + u ln(m0/m)
? = h/mv
4H + 2e- ? He +2? + 6?
U - ts = -tlog(Z)

34. Self Inductance
?scl = +/-1;?m = 0 - +/-1;?S_tot = 0;(?j = ?scl + ?S_tot)
V = -L di/dt
DS = 0 - dQ = 0 - P V^? = constant
X_C = 1/(i?C)

35. Magnetic field due to a segment of wire
1/2 CV²
B = µ0 I (sin(?1)-sin(?2))/(4pr) r = distance from point
(3/2) n R ?t
Let w_i = 1/s_i^2;x_wav = S(w_i x_i) / Sw_i - s_xwav = 1/Sw_i

36. Source Free RL Circuit
I = -(c ?t)^2 + d^2
DB = ( µ_0 I/(4Pi) ) dl(cross)rhat/r^2
? (t-vx/c²)
IR + Ldi/dt = 0 - I = I0e(-tL/R) Work = 1/2 L I0^2

37. Bohr Model: Radii
V = -L di/dt
N²/Z (m_elec/m_red)
?mv
ma + kx = 0

38. Quant: Orthogonality of States
W_A < W_I
ih_barL_z
<?1|?2> = 0 ? Orthogonal
1/ne - where n is charge carrier density

39. Ohm'S Law w/ current density
? = 5/3
µ = m_e/2
J = E s - s = Conductivity - E = Electric field
T = I?²/2

40. EM: Method of Images
.5 LI²
Opposing charge induced upon conductor
(° of Freedom)kT/2
Braking Radiation

41. Stefan-Boltzmann law for blackbodies (power per area and T)
?= h/v(2mE)
P/A = s T^4
P² ~ R³
?scl = +/-1;?m = 0 - +/-1;?S_tot = 0;(?j = ?scl + ?S_tot)

42. Volumetric Expansion
V = V0 + V0 a ?T
S_mean = s/Sqrt[N]
Infinitely close to equilibrium at all times
1/ne - where n is charge carrier density

43. Force/length between two wires
L = L_0 Sqrt[1-v^2/c^2]
Int ( A . dr) = Int ( del x A) dSurface
?scl = +/-1;?m = 0 - +/-1;?S_tot = 0;(?j = ?scl + ?S_tot)
µ0 I1I2 / (2pd)

44. Atom: Hydrogen Wave Function Type
Asin(?) = m?
Always Real
Exponentially decreasing radial function
1. Heat is energy 2. Entropy never decreases 3. Entropy approaches a constant value as t -> 0...

45. Lensmaker Equation - Thin Lens
1/f = (n-1)(1/R1 - 1/R2) if both positive - they are convex - concave
C_eq = ?C_i
E²-p²c²
N d flux / dt

46. Internal Energy of an Ideal Gas
(3/2) n R ?t
?mc²
?L/A - L = length - A = cross sectional area - rho is electrical resistivity
B = µ0 I (sin(?1)-sin(?2))/(4pr) r = distance from point

47. SR: Total Energy of a Particle
SR: ?=? - ß=? E = ?mc² = v(p²c² + m²c4)
dU = 0 ? dS = ?dW/T
Faraday/Lenz: current inducted opposes the changing field
1. Heat is energy 2. Entropy never decreases 3. Entropy approaches a constant value as t -> 0...

48. Lab: Precision of Measurements
1s² - 2s² 2p6 - 3s² 3p6 3d¹°
Measurements close to mean
? (t-vx/c²)
J = ? Fdt

49. Adiabatic means
µ=s^2
L = mr²d?/dt
I = I_0 Cos[?]^2
Isentropic

50. De Broglie wavelength
<T> = -<V>/2
X_L = X_C or X_total = 0
? = h/p
E²-p²c²