所屬科目:學士後西醫-物理
1. The horizontal surface on which the objects slide is frictionless. If M = 5.0 kg, the tension in string 1 is 60 N. Determine F. (A) 20 N (B) 24 N (C) 30 N (D) 34 N (E) 48 N
2. The mass in the figure slides on a frictionless surface. If m = 2 kg, k1 = 800 N/m, and k2 = 450 N/m, what is approximate the frequency of oscillation (in Hz)? (A) 2 (B) 4 (C) 6 (D) 8 (E) 10
3. A pivoted bar has a weight of 10 kg and a length of 1 meter, and is supported by a cable, as shown below. What is the tension force of the cable when a 50 N box is hung at the end of the bar? (A) 150 N (B) 295 N (C) 410 N (D) 570 N (E) 775 N
4. A circular track of radius 1000 meters is banked at 30 degrees without any friction. What is required speed for a car to keep running on the circular track? (A) about 30 m/s (B) about 45 m/s (C) about 55 m/s (D) about 65 m/s (E) about 75 m/s
5. Two point masses 1 kg and 2 kg are on a massless bar with axis of rotation through the center of length 2 meters, and a sphere of radius 10 cm and of mass 100 kg is on the center of the bar, as shown below. What is the moment of inertia (kg∙m2 )? (A) 3.33 (B) 3.4 (C) 3.5 (D) 3.67 (E) 4
7. The same force F is applied horizontally to bodies 1, 2, 3, and 4, of masses m, 2m, 3m, and 4m, initially at rest and on a frictionless surface, until each body has traveled distance d. The correct listing of the magnitudes of the velocities of the bodies, are . (A) (B) (C) (D) (E)
9. The superposition of two wavesand
13. A conductor of radius r, length ℓ , and resistivity ρ has resistance R. It is melted down and formed into a new conductor, also cylindrical, with one fourth the length of the original conductor. The resistance of the new conductor is . (A) R (B) R (C) R (D) 4 R (E) 16 R
14. There is an electric dipole in an electric field, as shown below. Which of the following statement is incorrect? (A) The dipole rotates clockwise. (B) The torque on +q points up. (C) The electric dipole moment is proportional to the distance from –q to +q. (D) The dipole has a max potential energy when it is perpendicular to E. (E) The electric dipole moment points from –q to +q.
31. A uniform solid ball with mass M is supported by a massless rod. Derive the period of the pendulum with a small displacement. (A) T = 2π(1.1L/g)1/2 (B) T = 2π(1.8L/g)1/2 (C) T = 2π(1.5L/g)1/2 (D) T = 2π(0.9L/g)1/2 (E) T = 2π(0.7L/g)1/2
34. A particle of mass m = 0.10 kg and speed v0 = 5.0 m/s collides and sticks to the end of a uniform solid cylinder of mass M = 1.0 kg and radius R = 20 cm. If the cylinder is initially at rest and is pivoted about a frictionless axle through its center, what is the final angular velocity (in rad/s) of the system after the collision? (A) 2.0 (B) 4.2 (C) 6.1 (D) 8.1 (E) 10
35. A set of pulleys is used for supporting the calf (100 N). Please determine the weight of the subject in the right hand side. (A) 50 N (B) 73 N (C) 100 N (D) 141 N (E) 173 N
39. A large tank of water has a hose connected to it. The tank is sealed at the top and has compressed air between the water surface and the top. When the water height h is 3.5 m the pressure of the compressed air is 4.0 x 105 Pa. Take the atmospheric pressure to be 1.0 x105 Pa. What is the speed of the water when it flows out of the hose if h is 3.5 m? (A) 30.8 m/s (B) 28.4 m/s (C) 26.8 m/s (D) 25.5 m/s (E) 23.4 m/s
51. Two isotopes leave the slit at point S and into a magnetic field of magnitude 0.100 T pointing into the page, each has speed of 1.00 x 106 m/s. The first one contain one proton and has a mass of 1.67 x 10-27 kg and the other contains a proton and a neutron and has a mass of 3.34 x 10-27 kg. What is the distance that they could be separated when they strike a photographic plate? (e = 1.6 x 10-19C) (A) 0.520 m (B) 0.313 m (C) 0.210 m (D) 0.105 m (E) 0.104 m
53. There are two point-charges −Q, and 2Q located at the distance 2d, and 4d from the origin O, respectively. What is the electric field at the origin O? (Vacuum permittivity is ε0) (A) 0 (B)E= (C)E= (D)E= (E)E=
54. There is a cylindrical conductor with radius R which carries current I. Which diagram is correct for the magnetic field of this conductor?
(A) (B) (C) (D) (E)
55. There are two parallel, straight current-carrying conductors with current I1 = 10 A and length I2 = 2 A. Both of these two conductors are 1 m length, and the distance between them is 2 m. What is the force between these two parallel conductors? (Permeability constant is μ0) (A) (B) (C) (D) (E)
60. In process ab, 20 J of heat is added to the system. In process bd, 80 J of heat is added to the system. Find the internal energy change ΔU in process abd. (A) 21 J (B) 59 J (C) 79 J (D) 101 J (E) 121 J