A/L 2001 Physics MCQ - Questions 51 - 60

51. A capacitor consists of n number of equally spaced, parallel conducting sheets. Alternate sheets connected together compose the positive plate, and the other alternate sheets compose the negative plate as shown in the figure. If A is the area of each sheet and d is the spacing between two adjacent sheets, the capacitance of the arrangement is
    
1. (1)
2. (2)
3. (3)
4. (4)
5. (5)
6. Answer with explanation
52. S₁, S₂, S₃
    
    and S₄ are four Gaussian surfaces drawn in the vicinity of two equal and opposite charges +q and -q as shown. The net electric flux through the surfaces S₁, S₂, S₃ and S₄ are represented by ϕ₁, ϕ₂, ϕ₃, and ϕ₄ respectively. Which of the following is correct?
1. (1) ϕ₁ = 0, ϕ₂ = 0, ϕ₃ = 0, ϕ₄ = 0
2. (2) ϕ₁ = 0, ϕ₂ > 0, ϕ₃ < 0, ϕ₄ = 0
3. (3) ϕ₁ > 0, ϕ₂ > 0, ϕ₃ < 0, ϕ₄ > 0
4. (4) ϕ₁ > 0, ϕ₂ > 0, ϕ₃ < 0, ϕ₄ = 0
5. (5) ϕ₁ < 0, ϕ₂ > 0, ϕ₃ < 0, ϕ₄ > 0
6. Answer with explanation
53. An ideal gas is taken through a cyclic process as shown in the P-V diagram.
    
    If Ub > Ua, consider the following statements.
1. (A) The net work done by the gas is positive for the whole process.
2. (B) Heat is absorbed along the path ab whereas heat is liberated along the path ba.
3. (C) The temperature of the gas at the beginning of the process is same as that at the end of the process.
   
4. Of the above statements
    
5. (1) only (A) is true
6. (2) only (A) and (B) are true
7. (3) only (A) and (C) are true
8. (4) only (B) and (C) are true
9. (5) all (A), (B) and (C) are true
10. Answer with explanation
54. Electrons are emitted from a certain metal when a monochromatic light of wavelength λ is incident on it. h is the Planck constant and c is the velocity of light. Consider the following statements.
1. (A) Kinetic energy of electrons emitted from the metal is less than hc/λ.
2. (B) Kinetic energy of electrons emitted from the metal does not depend on the material of the metal.
3. (C) Rate of emission of electrons depends on the wavelength λ.
4. Of the above statements,
    
5. (1) only (A) is true
6. (2) only (A) and (B) are true
7. (3) only (A) and (C) are true
8. (4) only (B) and (C) are true
9. (5) all (A), (B) and (C) are true
10. Answer with explanation
55. A mass is attached to the lower end of a vertical elastic string which is rigidly fixed at the other end. The mass is then moved downward with a constant velocity by applying a force F. The variation of F with time t is best represented by
1. (1)
2. (2)
3. (3)
4. (4)
5. (5)
6. Answer with explanation
56. The graph shows the variation of displacement (y) of an object with time (t).
    
    Which one of the following graphs best represents the variation of kinetic energy (K) of the object with time (t)?
1. (1)
2. (2)
3. (3)
4. (4)
5. (5)
6. Answer with explanation
57. The displacement (s) - time (t) curve of an object is shown in the figure.
    
    The corresponding velocity (v) - time (t) curve is best represented by
1. (1)
2. (2)
3. (3)
4. (4)
5. (5)
6. Answer with explanation
58. Two
    
    parallel long wires A and B carry identical currents in the same direction as shown in the diagram. Which of the following diagrams best represents the magnetic flux in a plane perpendicular to the wires?
1. (1)
2. (2)
3. (3)
4. (4)
5. (5)
6. Answer with explanation
59. A
    
    U-tube contains a liquid as shown in the figure. When the tube is moved horizontally to the right with a constant acceleration a, the difference in the heights of liquid columns in the limbs is
1. (1)
2. (2)
3. (3)
4. (4)
5. (5)
6. Answer with explanation
60. A
    
    long wire ABC is bent to form 60° angle and kept in a plane perpendicular to a uniform magnetic field as shown in the figure. Another long straight wire PQ made of the same material with the same cross-sectional area is pulled with a constant velocity on the wire ABC, so that the triangle RBS is always equilateral. The induced current (I) in the triangle RBS varies with time (t) as
1. (1)
2. (2)
3. (3)
4. (4)
5. (5)
6. Answer with explanation

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A/L 2001 Physics MCQs: 1 - 10 | 11 - 20 | 21 - 30 | 31 - 40 | 41 - 50 | 51 - 60