Test your basic knowledge |

GRE Physics

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
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 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)
0
?s = 0 - ?l = ±1
L = mr²d?/dt

2. Mech: Impulse
E = s/e_0
P/A = s T^4
J = ? Fdt
T = I?²/2

3. Energy in terms of partition function
DW/dq
U = t^2 d/dt (logZ)
<?1|?2> = 0 ? Orthogonal
?mc²

4. Angular momentum - Central Force Motion
L = mr²d?/dt
Triplet: symmetric - net spin 1 Singlet: antisymmetric - net spin 0
u dm/dt
IR + Ldi/dt = 0 - I = I0e(-tL/R) Work = 1/2 L I0^2

5. Lab: Standard Deviation of Poisson
N²/Z (m_elec/m_red)
.5 LI²
KE = 1/2 * µ (dr/dt)² L = µ r x v
v(mean)

6. Thermo: 1st Law
?max = 2.898 x 10 -³ / T
dQ = dW +dU
I = I_cm + (1/2)m d^2
1/f = (n-1)(1/R1 - 1/R2) if both positive - they are convex - concave

7. Law of Mass Action
Product ( nj ^ vj ) = Product(nqj ^ vj exp (-vj F(int)/Tau))
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
S = k ln[O] ; dS = dQ/T
1/f = (n-1)(1/R1 - 1/R2) if both positive - they are convex - concave

8. Malus Law

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

9. Bohr Model: Radii
µ0 I / 2pR
N²/Z (m_elec/m_red)
? = ?0 root((1-v/c)/(1+v/c))
Dp/dt = L / (t ?V)

10. Pauli matrices
0
(3/2) n R ?t
J = ? Fdt
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

11. Thermo: Blackbody Radiation
qvb = mv²/R
W_A < W_I
F = s * T4
P = µ_0 q^2 a^2/(6Pi c); No radiation along the axis of acceleration

12. Springs in series/parallel
Cv = dE/dT = 3R
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...
Series: 1/k_eq = 1/k_1 + 1/k_2; Parallel: k_eq = k_1 + k_2

13. Astro: p-p Chain
4H + 2e- ? He +2? + 6?
I = I_0 Cos[?]^2
V = -L di/dt
1/2 CV²

14. Lab: Precision of Measurements
Measurements close to mean
F = s * T4
F = R/2
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

15. Heat added
? = ?_0 Sqrt[(1+v/c)/(1-v/c)]
I_z = I_x + I_y (think hoop symmetry)
NC?T
S_mean = s/Sqrt[N]

16. Magnetic Field For Current in Long Wire
µ0 I / 2pR
Int ( A . dr) = Int ( del x A) dSurface
J = ? Fdt
U = t^2 d/dt (logZ)

17. Entropy (# of states - and in terms of other thermo quantities)
S = k ln[O] ; dS = dQ/T
?_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
1/vLC

18. Quant: Expectation Value
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> = -<V>/2
<?|O|?>
µ0 I1I2 / (2pd)

19. Atom: Hydrogen Wave Function Type
Exponential - E = -ma²/2hbar² - a is strength of delta wellt
Exponentially decreasing radial function
IR + Ldi/dt = 0 - I = I0e(-tL/R) Work = 1/2 L I0^2
Infinitely close to equilibrium at all times

20. EM: Maxwell'S equations
E = Vmin : circle - E = 0 : parabola - E<0 : el - E>0 : h
F = qv×B
<T> = 1/2 * <dV/dx>
div(E) = ?/e_0 - curl(E) = der(B)/der(t) - div(B) = 0 - curl(B) = µ_0J + µ_0e_0*der(E)/der(t)

21. Astro: Kepler'S Third Law
E²-p²c²
W_A < W_I
P² ~ R³
? (t-vx/c²)

22. Anomalous Zeeman Effect

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

23. Hamiltonian and Hamilton'S equations
DB = ( µ_0 I/(4Pi) ) dl(cross)rhat/r^2
H = T + V;qdot_i = dH/dp_i - pdot_i = dH/dq_i
X_L = X_C or X_total = 0
v(mean)

24. Work in a capacitor
P1V1 - P2V2 / (? - 1)
1/2 CV²
P(s) = (1/Z) Exp[-E(s)/(k T)] Z = S_s(Exp[-E(s)/(k T)])
? = h/p

25. Lagrangian and Lagrange'S equation
E = <?| H |?>
1/ne - where n is charge carrier density
u dm/dt
L = T - V dL/dq = d/dt dL/dqdot

26. Weighted average (mean and unc. of mean)
Triplet: symmetric - net spin 1 Singlet: antisymmetric - net spin 0
v(mean)
Let w_i = 1/s_i^2;x_wav = S(w_i x_i) / Sw_i - s_xwav = 1/Sw_i
? = ?0 root((1-v/c)/(1+v/c))

27. Relativistic Energy
?mc²
F_f = µ*F_N
1/2 CV²
C = 4pe0 ab/(a-b) = inner and outer radii

28. De Broigle Wavelength
? = h/mv
P1V1 - P2V2 / (? - 1)
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
1. Heat is energy 2. Entropy never decreases 3. Entropy approaches a constant value as t -> 0...

29. Relativistic interval (which must remain constant for two events)
I = -(c ?t)^2 + d^2
T = I?²/2
Z²/n² (m_red/m_elec)
DW/dq

30. Bragg'S Law of Reflection
M? = 2dsin(?)
N d flux / dt
? exp(-e/t)
SR: ?=? - ß=? E = ?mc² = v(p²c² + m²c4)

31. Error in the mean if each measurement has the same uncertainty s
I = -(c ?t)^2 + d^2
U - ts = -tlog(Z)
Let w_i = 1/s_i^2;x_wav = S(w_i x_i) / Sw_i - s_xwav = 1/Sw_i
S_mean = s/Sqrt[N]

32. Center of Mass: Kinetic Energy & Angular Momentum
Always Real
A[B -C] = A[B -C]+[B -A]C [A -B] = -[B -A]
X_C = 1/(i?C)
KE = 1/2 * µ (dr/dt)² L = µ r x v

33. EM: Reactance of Capacitor
X_C = 1/(i?C)
Faraday/Lenz: current inducted opposes the changing field
Asin(?) = m?
N²/Z (m_elec/m_red)

34. Thermo: Isothermal
dU = 0 ? dS = ?dW/T
P +1/2 ? v² + ?gh = Constant
Dp/dt = L / (t ?V)
C_eq = (? 1/C_i)^-1

35. Force exerted on charge by long wire
C_eq = ?C_i
DB = ( µ_0 I/(4Pi) ) dl(cross)rhat/r^2
X_C = 1/(i?C)
F = µ0 q v I / 2pr

36. Solid: Resistivity of Semi-Conductor
L = mr²d?/dt
I = I_0 Cos[?]^2
?~1/T
I = I_cm + (1/2)m d^2

37. First law of thermodynamics (explain direction of energy for each term)
?~T
Q = U + W Q = heat in system - U = total energy in system - W = work done by gas
Product ( nj ^ vj ) = Product(nqj ^ vj exp (-vj F(int)/Tau))
Z_C + Z_L = 0. Occurs when ?=1/Sqrt[L C]

38. Mean electron drift speed
P(s) = (1/Z) Exp[-E(s)/(k T)] Z = S_s(Exp[-E(s)/(k T)])
DS = 0 - dQ = 0 - P V^? = constant
J/(ne) n: atom density
µ0 I1I2 / (2pd)

39. QM: de Broglie Wavelength
1/2 CV²
?= h/v(2mE)
F = mv²/r
<T> = 1/2 * <dV/dx>

40. Kepler'S third law (T and R)
Always Real
P(s) = (1/Z) Exp[-E(s)/(k T)] Z = S_s(Exp[-E(s)/(k T)])
L = L_0 Sqrt[1-v^2/c^2]
T^2 = k R^3 - k=constant

41. Bohr Model: Energy
Z²/n² (m_red/m_elec)
Exp(N(µ-e)/t)
X_L = X_C or X_total = 0
.5 LI²

42. Doppler Shift in Frequency
SR: ?=? - ß=? E = ?mc² = v(p²c² + m²c4)
E = Z²*E1
?~T
F = f* (c+v_r)/(c+v_s)

43. Resistance - length - area - rho
CdV/dt + V/R = 0 V(t) = V0 exp(-t/RC) I(t) = I(0) exp(-t/RC)
S = k ln[O] ; dS = dQ/T
H = H_0 + ?H
?L/A - L = length - A = cross sectional area - rho is electrical resistivity

44. Relativistic length contraction
L = L_0 Sqrt[1-v^2/c^2]
<T> = 1/2 * <dV/dx>
J = E s - s = Conductivity - E = Electric field
A[B -C] + [A -C]B

45. Magnetic Dipole Moment and Torque
µ = Current * Area T = µ x B
1s² - 2s² 2p6 - 3s² 3p6 3d¹°
µ0 I / 2pR
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

46. EM: Lorentz Force
DS = 0 - dQ = 0 - P V^? = constant
F = qv×B
Product ( nj ^ vj ) = Product(nqj ^ vj exp (-vj F(int)/Tau))
P/A = s T^4

47. Quant: Orthogonality of States
Hbar*?³/(p²c³exp(hbar?/t)-1)
qvb = mv²/R
<?1|?2> = 0 ? Orthogonal
Ct²-x²-y²-z²

48. Planck Radiation Law
F = qv×B
Hbar*?³/(p²c³exp(hbar?/t)-1)
P1V1 - P2V2 / (? - 1)
E²-p²c²

49. EM: Reactance of Inductor
.5 CV²
?= h/v(2mE)
X_L = i?L
North to south; Earth has S magnetic pole at the N geographic pole and vice versa.

50. Charge in Capacitor
Q = CVexp(-t/RC)
0
E = Z²*E1
µ=s^2