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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. Focal point of mirrror with curvature
F = R/2
?= h/v(2mE)
V(r) + L²2/2mr²
Exponential - E = -ma²/2hbar² - a is strength of delta wellt

2. Relativistic length contraction
PdV +dU
? (t-vx/c²)
L = L_0 Sqrt[1-v^2/c^2]
1. Heat is energy 2. Entropy never decreases 3. Entropy approaches a constant value as t -> 0...

3. Doppler Shift for light
? = 1.22? / d
? = ?0 root((1-v/c)/(1+v/c))
M? = 2dsin(?)
? = ?_0 Sqrt[(1+v/c)/(1-v/c)]

4. Atom: Orbital Config
DS = 0 - dQ = 0 - P V^? = constant
Triplet: symmetric - net spin 1 Singlet: antisymmetric - net spin 0
1s² - 2s² 2p6 - 3s² 3p6 3d¹°
<T> = 1/2 * <dV/dx>

5. Addition of relativistic velocities

6. Relativistic interval (which must remain constant for two events)
E_n = -µ c^2 Z a^2 / (2n^2) - with µ = m_1 m_2 / (m_1 + m_2)
Measurements close to true value
L = µ N² A / l : N = number of turns - A = cross sectional area -l = length
I = -(c ?t)^2 + d^2

7. Quant: [L_x -L_y] = ?
J/(ne) n: atom density
L^2 |E - scl - m> = hbar^2 scl(scl+1) |E -scl -m> L_z |E - scl - m> = hbar m |E - scl - m>
W_A < W_I
ih_barL_z

8. Volumetric Expansion
?= h/v(2mE)
F = µ0 q v I / 2pr
B = µ0 I (sin(?1)-sin(?2))/(4pr) r = distance from point
V = V0 + V0 a ?T

9. Radiation (Larmor - and another neat fact)
Isentropic
J = E s - s = Conductivity - E = Electric field
P = µ_0 q^2 a^2/(6Pi c); No radiation along the axis of acceleration
Measurements close to mean

10. EM: Bremsstrahlung (translation)
U - ts = -tlog(Z)
Braking Radiation
I = Im (sinc²(a)) ; a = pai sin(?) / ?
F = -2*m(? x r)

11. Bohr Model: Energy
? = h/p
F = f* (c+v_r)/(c+v_s)
I = I_cm + md²
Z²/n² (m_red/m_elec)

12. Charge in Capacitor
?mc²
F = qv×B
1/f = (n-1)(1/R1 - 1/R2) if both positive - they are convex - concave
Q = CVexp(-t/RC)

13. Time Lorentz Transformation
P1V1 - P2V2 / (? - 1)
? (t-vx/c²)
Let w_i = 1/s_i^2;x_wav = S(w_i x_i) / Sw_i - s_xwav = 1/Sw_i
Const: 2t = (n +.5)? Destructive 2t = n?

14. EM: Electric Field inside of Conductor
v(mean)
0
J = ? Fdt
J/(ne) n: atom density

15. EM: SHO (Hooke)
ma + kx = 0
F = f* (c+v_r)/(c+v_s)
I = -(c ?t)^2 + d^2
µ = m_e/2

16. Astro: Aperture Formula (Rayleigh Criterion)
? = 1.22?/D
V = -L di/dt
X_C = 1/(i?C)
? = ?_0 Sqrt[(1+v/c)/(1-v/c)]

17. Single Slit Diffraction Maximum
SR: ?=? - ß=? E = ?mc² = v(p²c² + m²c4)
North to south; Earth has S magnetic pole at the N geographic pole and vice versa.
Asin(?) = m?
Ct²-x²-y²-z²

18. Effective Potential
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
<T> = -<V>/2
V(r) + L²2/2mr²
P² ~ R³

19. De Broigle Wavelength
u dm/dt
? = h/mv
A[B -C] + [A -C]B
µ0 I / 2R

20. Bohr Model: Radii
dQ = dW +dU
C_eq = ?C_i
F = qv×B
N²/Z (m_elec/m_red)

21. td(entropy) =
PdV +dU
J/(ne) n: atom density
? = 5/3
E_n = -µ c^2 Z a^2 / (2n^2) - with µ = m_1 m_2 / (m_1 + m_2)

22. Thermo: Blackbody Radiation
1/ne - where n is charge carrier density
F = s * T4
u dm/dt
Asin(?) = m?

23. Atom: Positronium Reduced Mass
F = µ0 q v I / 2pr
F = s * T4
?~1/T
µ = m_e/2

24. Energy in Inductor
Interference: (m+.5)? = d sin(?) Diffraction: m? = w sin(?)
µ0 I / 2pR
.5 LI²
H = H_0 + ?H

25. Force/length between two wires
S_mean = s/Sqrt[N]
<T> = -<V>/2
µ0 I1I2 / (2pd)
Braking Radiation

26. First law of thermodynamics (explain direction of energy for each term)
S = k ln[O] ; dS = dQ/T
Q = U + W Q = heat in system - U = total energy in system - W = work done by gas
PdV +dU
C_eq = (? 1/C_i)^-1

27. QM: de Broglie Wavelength
Z = ?g_i*exp(-E/kT)
?= h/v(2mE)
S = k ln[O] ; dS = dQ/T
4H + 2e- ? He +2? + 6?

28. Dulong Petit Law
Cv = dE/dT = 3R
B = µ0 I n
?mv
4H + 2e- ? He +2? + 6?

29. Mech: Force of Friction
F_f = µ*F_N
S = k ln[O] ; dS = dQ/T
qvb = mv²/R
B = µ0 I (sin(?1)-sin(?2))/(4pr) r = distance from point

30. Virial Theorem
<T> = 1/2 * <dV/dx>
Always Real
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.
?~T

31. Selection rules for atomic transitions
I_z = I_x + I_y (think hoop symmetry)
Braking Radiation
dQ = dW +dU
?scl = +/-1;?m = 0 - +/-1;?S_tot = 0;(?j = ?scl + ?S_tot)

32. Clausius-Clapeyron Equation
Dp/dt = L / (t ?V)
Hbar*?³/(p²c³exp(hbar?/t)-1)
B = µ0 I n
<?|O|?>

33. Lab: Precision of Measurements
µ0 I / 2R
Measurements close to mean
Hbar*?³/(p²c³exp(hbar?/t)-1)
1s² - 2s² 2p6 - 3s² 3p6 3d¹°

34. EM: Reactance of Inductor
Cv = dE/dT = 3R
Sin(?) = ?/d
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.
X_L = i?L

35. Center of Mass: Kinetic Energy & Angular Momentum
V(r) + L²2/2mr²
DB = ( µ_0 I/(4Pi) ) dl(cross)rhat/r^2
L = mr²d?/dt
KE = 1/2 * µ (dr/dt)² L = µ r x v

36. Anomalous Zeeman Effect

37. Coriolis Force
F = -2*m(? x r)
Cos[?] Sin[?] -Sin[?] Cos[?]
?max = 2.898 x 10 -³ / T
T^2 = k R^3 - k=constant

38. Stefan-Boltzmann law for blackbodies (power per area and T)
?scl = +/-1;?m = 0 - +/-1;?S_tot = 0;(?j = ?scl + ?S_tot)
Q = U + W Q = heat in system - U = total energy in system - W = work done by gas
P/A = s T^4
B = µ0 I (sin(?1)-sin(?2))/(4pr) r = distance from point

39. Lensmaker Equation - Thin Lens
N²/Z (m_elec/m_red)
? = 5/3
1/f = (n-1)(1/R1 - 1/R2) if both positive - they are convex - concave
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.

40. Springs in series/parallel
A[B -C] + [A -C]B
Dp/dt = L / (t ?V)
M? = 2dsin(?)
Series: 1/k_eq = 1/k_1 + 1/k_2; Parallel: k_eq = k_1 + k_2

41. Resonance frequency of LC circuit
North to south; Earth has S magnetic pole at the N geographic pole and vice versa.
1/vLC
L = µ N² A / l : N = number of turns - A = cross sectional area -l = length
D/dt (.5*r^2 d?/dt) = 0 - r(?) = a(1-e²)/(1+ecos(?)) - T²aA³

42. Adiabatic processes (dS - dQ - P and V)
1/f = (n-1)(1/R1 - 1/R2) if both positive - they are convex - concave
1. Heat is energy 2. Entropy never decreases 3. Entropy approaches a constant value as t -> 0...
DS = 0 - dQ = 0 - P V^? = constant
NC?T

43. EM: Method of Images
<?|O|?>
v(mean)
Opposing charge induced upon conductor
?scl = +/-1;?m = 0 - +/-1;?S_tot = 0;(?j = ?scl + ?S_tot)

44. Kepler'S Three Laws
D/dt (.5*r^2 d?/dt) = 0 - r(?) = a(1-e²)/(1+ecos(?)) - T²aA³
PdV +dU
I = V/R exp(-t/RC)
1/ne - where n is charge carrier density

45. Self Inductance
E ~ (1/(n_f)² - 1/(n_i)²) ~ 1/?
F = I L X B
?~1/T
V = -L di/dt

46. Thermo: Monatomic gas ?=?
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
? = 5/3
Let w_i = 1/s_i^2;x_wav = S(w_i x_i) / Sw_i - s_xwav = 1/Sw_i
Sin(?) = ?/d

47. Electromotive Force
Measurements close to mean
DW/dq
L = T - V dL/dq = d/dt dL/dqdot
Q = CVexp(-t/RC)

48. Complex impedance (expressions for capacitor and inductor)
SR: ?=? - ß=? E = ?mc² = v(p²c² + m²c4)
I = -(c ?t)^2 + d^2
N d flux / dt
Z_c = -i/(?C) ; Z_L = i ? L

49. 3 Laws of Thermo
µ0 I / 2R
4H + 2e- ? He +2? + 6?
1. Heat is energy 2. Entropy never decreases 3. Entropy approaches a constant value as t -> 0...
E = Vmin : circle - E = 0 : parabola - E<0 : el - E>0 : h

50. Bernoulli Equation
Isentropic
1s² - 2s² 2p6 - 3s² 3p6 3d¹°
P +1/2 ? v² + ?gh = Constant
qvb = mv²/R