57. What is the electric flux through a surface in between two parallel planes shown in the figure if w = 2 cm, l = 5 cm, E = 500 N/C and θ = 30°?

(A) 0.52 N⋅m² /C
(B) 0.26 N⋅m² /C
(C) 0.81 N⋅m² /C
(D) 0.43 N⋅m² /C
(E) 0.36 N⋅m² /C

53. Two parallel thin planes of charge electrical charge density 2.5✖108 C/m2 . What is the electric field in the region between the two planes? Assume that the vacuum electric permittivity is (A) (B) (C) (D) (E)

54. The voltage across a parallel-plate capacitor is measured to be 92.5 V. When a dielectric is inserted between the plates, the voltage drops to 23.4 V. What is the dielectric constant of the inserted material? Assume that the vacuum electric permittivity is (A) 0.26 (B) 2.64 (C) 0.62 (D) 3.95 (E) 1.82

55. An AC generator consists of 6 turns of a wire. Each turn has an area of 0.040 m2 . The loop rotates in a uniform field (B = 0.20 T) at a constant frequency of 50 Hz. What is the maximum induced emf? (A) 2.4 V (B) 3.0 V (C) 4.8 V (D) 13 V (E) 15 V

56. It is known that the magnetic field of 0.17 T can cause an ion to move in a circular orbit of radius 2 m. Find the radius of circular orbit of a ion with identical velocity in the same magnetic field. (Ion moves in direction perpendicular to the magnetic field.) (A) 0.12 m (B) 0.25 m (C) 0.34 m (D) 0.52 m (E) 0.72 m

58. A solenoid with 200 turns of copper wires is operated by a 1000 V power supply and must be 25 cm long. What is the magnitude of magnetic field that is created in the solenoid? (The resistance of Cu wire is 0.2 Ω and the permeability T⋅m/A) (A) 5.03 T (B) 3.21 T (C) 7.84 T (D) 4.58 T (E) 4.36 T

59. For a convex mirror with radius of curvature R = 10 cm, if an object is placed 15 cm in front the mirror, what is the magnification of the image and is it a real or virtual? Upright or inverted? (mirror’s equation: 1/p+1/q = 2/R) (A) 3.75 cm (virtual behind mirror) and M = 0.25, inverted (B) 7.50 cm (virtual behind mirror) and M = 0.5, upright (C) 3.75 cm (real in front mirror) and M = 0.5, inverted (D) 7.50 cm (real in front mirror) and M = 0.25, inverted (E) 3.75 cm (virtual behind mirror) and M = 0.25, upright

複選題60. For a bi-concave thin lens, the radii of curvature are 10 and 20 cm. If an object is placed 15 cm in front of the mirror, what is the magnification of the image and is it a real or virtual? Upright or inverted? (thin lens’ equation: 1/p+1/q = (n−1)(1/R1−1/R2), the refractive index of glass is 1.5). (AB) 9.72 cm (virtual behind mirror) and M = 0.64, inverted (AC) 11.64 cm (virtual behind mirror) and M = 0.58, inverted (AD) 10.91 cm (virtual in front mirror) and M = 0.73, upright (AE) 8.69 cm (real in front mirror) and M = 0.25, inverted (BC) 12.45 cm (virtual behind mirror) and M = 0.53, upright (BD)一律送分

61. Select the answer with the correct number of decimal places for the following sum: 13.914 cm + 243.1 cm + 12.00460 cm = (A) 269.01860 cm (B) 269.0186 cm (C) 269.019 cm (D) 269.02 cm (E) 269.0 cm

62. Detection of radiation by a Geiger-Müller counter depends on ______. (A) the emission of a photon from an excited atom (B) the ability of an ionized gas to carry an electrical current (C) the emission of a photon of light by the radioactive particle (D) the ability of a photomultiplier tube to amplify the electrical signal from a phosphor (E) the detection of the sound made by decay particles

63. Please calculate the ΔS if ΔHvap is 66.8 kJ/mol, and the boiling point is 83.4°C at 1 atm, when the substance is vaporized at 1 atm. (A) -187 J/K mol (B) 187 J/K mol (C) 801 J/K mol (D) -801 J/K mol (E) 0